MCP

Sending operations — Volumes, schedules, rotation and pause thresholds, with the thinnest evidence in the library flagged page by page

The mechanics of executing a campaign safely once its content exists: when to send, how much per mailbox and how fast to get there, how to spread load across senders, what to check before going live, and when to stop.

An honesty note this module keeps in view: the evidence here is thinner than anywhere else in the library. Almost every number comes from a sending platform's own guidance, with no independent corpus and no counter-school to argue with it. Two of the most-repeated claims in this area did not survive being checked against their own sources — the widely quoted "Tuesday to Thursday, 9-11am" timing rule, and a per-mailbox daily limit that two pages of the same vendor state five-fold apart. The pages below say so where it applies. Treat these numbers as starting points to test rather than as laws, and weight the asymmetry: too little volume costs pipeline, too much costs a domain.

The pages:

  • Send windows and timezones — Why the "Tuesday to Thursday, 9-11am" rule traces to a source that disowns it, and the parts that survive: recipient-timezone working hours, held constant.
  • Volume limits and ramp — The four-week ramp every source agrees on, a ceiling one vendor states fivefold apart (30-50 vs 100-250 a day), and what Google's 5,000-a-day line is not.
  • Throttling and rotation — Three to five rotated mailboxes on secondary domains, the per-mailbox cap that sums across campaigns, and send-spacing jitter as convention without evidence.
  • Pre-launch QA — List, rendering and identity checks: the 2% bounce tolerance, the real self-send that previews cannot replace, and what a placement test cannot prove.
  • Campaign scheduling and pausing — Bounce and complaint rates as the two daily numbers, the 2% and 0.05% pause thresholds, and recovery timelines up to twelve weeks that argue for stopping early.

What the touches say is Sequences and follow-ups; why placement works the way it does is Deliverability and compliance essentials.