A gap in registration will queue up many activities that take a long time to flush

[dblock]

If a bot was installed on trial, then paused because trial expired, and paid for much later, there is a long backlog of activities. These take a long time to flush, making the bot seem stale. A few options:

a) Flush those immediately upon registration (may be a lot)?
b) Flush only if there's a reasonable amount.
c) Give the admin the ability to see how many backlogged activities there are and the ability to flush them or cancel them.
d) Don't flush but inform the users that there's a lot of backlogged activities to flush.