Independent coverage of the full email ecosystem.
Deliverability · Breaking
Apple's upcoming iOS 26 is expanding Link Tracking Protection — currently in Safari Private Browse mode — to the native Mail and Messages apps. URLs clicked in Apple Mail will have common tracking parameters automatically stripped before the click is registered. That includes utm_, gclid, dclid, and similar identifiers.
This is different from Mail Privacy Protection. MPP broke open tracking. iOS 26 LTP breaks click attribution. If a subscriber clicks a link in Apple Mail, you'll still register the click — but you won't know which campaign, source, or medium drove it, unless you've implemented server-side tracking or first-party attribution. Apple Mail commands roughly 50–60% of mobile opens in many B2C programs.
The migration path: first-party attribution, server-side tracking, and reducing reliance on platform-specific click IDs in favor of UTM-based measurement.
Sources: emailexpert · HMA · MarTech
Deliverability · AI & Email · Major Development
Google's January 2026 Gmail overhaul — powered by Gemini 3 — is still rolling out and its deliverability implications are becoming clearer. The new AI Inbox view reshapes Gmail around summaries, topics, and to-dos rather than individual messages. An email can land in the inbox and still go unseen.
Measured impact: CTR dropped from approximately 4.35% to 3.93% following the AI summary rollout. Up to 40% of emails reaching Gmail inboxes are reportedly being deprioritized by AI filtering. Content quality is now a direct deliverability signal: Gmail's AI evaluates clarity, structure, and value density.
Sources: Google Blog · emailexpert · Folderly · RMA
Infrastructure · Update
Last week's issue flagged April 30 as the hard deadline for Microsoft to fully retire Basic Authentication for SMTP AUTH. That was wrong — Microsoft moved the deadline.
On January 27, 2026, Microsoft revised the timeline: SMTP AUTH Basic Authentication behavior is unchanged through the end of December 2026. The March 1 soft rollout appears to have been paused as part of the extension. If you published or forwarded the April 30 deadline, a correction is in order. The migration path is the same — OAuth 2.0, High Volume Email, or Azure Communication Services — but the urgency has been reset by eight months.
Sources: Microsoft Tech Community (original) · Updated timeline · Office365ITPros
Infrastructure · AI & Email
During Cloudflare Agents Week (April 9–16), Cloudflare moved its Email Service from private to public beta. This is email infrastructure built natively for AI agents, not for humans. Developers can now send and receive email directly from Cloudflare Workers via a native binding, with no API keys, secrets management, or separate SMTP configuration.
An AI agent can receive an email, spend an hour processing external data across multiple systems, and send a fully composed reply — all within native Cloudflare infrastructure. Cloudflare developer Thomas Gauvin also open-sourced Agentic Inbox — a self-hostable email client with a built-in AI agent running on Workers.
Sources: Cloudflare Blog · Agents Week in Review · Agentic Inbox
Security · Research
Sublime Security released its 2026 Email Threat Research Report. Key findings:
BEC and fraud attacks: 32% of all email threats in 2025
Thread hijacking: 28.1% of all BEC attacks — the single largest technique
34.7% of attacks used two or more evasion techniques in the same campaign
32.8% of attacks leveraged uncommon trusted platforms (LOTS: Jotform, Typeform, WeTransfer, Notion, Airtable) rather than obvious malicious infrastructure
Callback phishing surged 500% in Q4 2025
The through-line: attackers exploit trust. They use your legitimate tools, your email threads, your vendors' infrastructure. Authentication-based filtering sees none of it.
Sources: Key Findings · Full Report
Security · Platforms
On April 15, Bitdefender launched GravityZone Extended Email Security: a dual-layer product combining a traditional secure email gateway (SEG) with API-based post-delivery protection (ICES). SEG filtering catches threats before delivery; the API layer monitors inboxes after delivery and remediates what got through. Connects to Microsoft 365 via Microsoft Graph API — no MX record changes, live within minutes. Bitdefender claims 3x more BEC and credential phishing caught versus traditional methods.
Sources: Help Net Security · Bitdefender
EvilTokens is a PhaaS kit sold via Telegram since mid-February 2026, targeting Microsoft 365 via device code phishing — explicitly designed to bypass MFA. The attack initiates Microsoft's legitimate device code auth flow; when the victim enters the code, they unknowingly authorize the attacker's session. No credentials captured, no MFA to bypass.
Microsoft Defender: 10–15 distinct campaigns launching every 24 hours since March 15. Each campaign is AI-assisted. Hundreds of Microsoft 365 organizations compromised daily. Gmail and Okta variants in development.
Sources: Microsoft Security Blog · BleepingComputer · Sekoia · The Register
Since October 2025, threat actors have been embedding n8n webhook URLs in phishing emails — volume in March 2026 was 686% higher than January 2025. A LOTS attack using legitimate workflow automation to evade email filtering.
A second variant: invisible tracking pixels force the victim's email client to send an HTTP GET to the webhook automatically, capturing IP address and device telemetry without any click. Enables target profiling before the actual attack.
Sources: The Hacker News · Talos
Vercel breach via third-party AI OAuth — Context.ai compromise through Google Workspace OAuth exposed 580 Vercel employee records and customer env vars. OAuth-connected AI tools are a live attack surface; env var exposure is a common first step to SMTP credential compromise. Vercel
DMARC adoption: still dismally low — Only 10.7% of domains have strict reject policy at 100% enforcement. 70.9% of domains have no effective DMARC protection at all. PowerDMARC
Spam Resource: The case for reactivation (and sunsetting) — Carrying disengaged subscribers hurts inbox placement for everyone. Spam Resource
In March, AgentMail closed a $6M seed round led by General Catalyst, with YC participation and angels including Paul Graham, Dharmesh Shah, Paul Copplestone, and Karim Atiyeh. AgentMail gives AI agents their own email inboxes via REST API — two-way conversations, threading, labeling, searching, and replying.
Demand signal: when OpenClaw launched in late January 2026, AgentMail's user count tripled that week and quadrupled in February.
Sources: TechCrunch · Globe Newswire
Extra AI Email App launches with $9.5M — Consumer AI email app from three Pinterest veterans; launched publicly April 21. Joins Shortwave, Notion Mail, and Copilot inbox in the AI-native email client race. Upstarts Media
Microsoft Copilot: autonomous email delegation in development — Copilot mode that independently responds to and manages emails without step-by-step user approval. No ship date yet; governance controls planned. Windows News AI
On March 31, Postmark announced the completion of its migration from PowerMTA to KumoMTA — every email Postmark sends now runs through KumoMTA. Postmark is a well-regarded transactional ESP; its public migration validates KumoMTA's readiness as a PowerMTA replacement in production ESP environments. Improved queue times reported across Gmail, Yahoo, Microsoft, and Apple.
Sources: Postmark Blog · KumoMTA Spring 2026 Release · 2026 MTA Buyers Guide
KumoMTA 2026 State of MailOps Report — Core finding: MailOps didn't get more complicated — it got less forgiving. Legacy assumptions about retries, reputation recovery, and safe defaults no longer hold. KumoMTA
Namecheap: scheduled email infrastructure maintenance April 27–30 — No downtime expected, but slower response times and auth delays possible. Flag this if your clients use Namecheap private email hosting. Namecheap
EU AI Act: ~102 days to full enforcement — Full applicability August 2, 2026. No subliminal manipulation in AI-driven personalization for EU audiences; transparency for AI-generated content; penalties up to 7% of global annual turnover. emailexpert
Australia ACMA enforcement ramping — ACMA penalties for email and SMS compliance violations in 2025–2026. Worth tracking if your audience has ANZ segments. emailexpert
Just Wrapped
Festival of Email Barcelona — Deliverability Summit (Apr 20–22) + Sender Symposium (Apr 24)
Unspam Long Beach (Apr 20–22)
Adobe Summit Las Vegas (Apr 19–22)
Coming Up
POSSIBLE Miami Beach (Apr 27–29)
Twilio SIGNAL, San Francisco (May 6–7)
ANA Email Evolution Conference, Chicago (May 14)
The Newsletter Conference (May 15)
Inbox Expo 2026, Atlanta GA (May 26–28)
M3AAWG 67th General Meeting, Montréal (Jun 8–11) — CFP deadline May 11
M3AAWG Paris (Oct 26–29) — CFP deadline August 31
emailexpert: Apple's iOS 26 Privacy Updates — What Email Marketers Need to Know
RMA: Gmail Deliverability in the Gemini Era — Delivered Doesn't Mean Seen
Office365ITPros: SMTP AUTH Client Submission Retirement Delayed
Sublime Security: Key Findings from the 2026 Email Threat Research Report
Postmark: We Migrated to KumoMTA — Here's Why It Matters for You
TechCrunch: AgentMail Raises $6M to Build an Email Service for AI Agents
The Hacker News: n8n Webhooks Abused for Malware Distribution
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