What is inbox rotation?
Inbox rotation is a sending schedule in which inboxes are split into batches that take turns: each batch sends for a few days, then rests while the others carry the volume. The daily emails are shared across whichever inboxes are sending that day, so the load on each one depends on the pattern you choose.
Reading the result
The calendar shows every day of the period and which batches send or rest on it. Batches are staggered round the cycle so their rest days fall apart. If you give a daily volume, each day shows how many emails each sending inbox carries, and the per-inbox table adds up its sending days, rest days and planned emails. The CSV has one row per inbox per day, ready for a spreadsheet.
What to watch for in a rotation
Days when nobody sends
With few batches and long rests, every batch can be resting on the same day. The planner counts those days and flags them, because the volume either waits or lands on the next day.
The load moving instead of shrinking
Resting a batch does not reduce the daily volume. The same emails go out through fewer inboxes, so each sending inbox carries more on those days. Check the emails per inbox column against your own limit.
Weekends counted as rest
Here a day you do not send on is skipped, not counted as rest. If you count weekends as rest days in your own tool, the two schedules will drift apart.
Uneven batches
When the inboxes do not divide evenly, some batches have one more inbox than others, so the number sending changes from day to day. The batch list shows each size.