The capture queue read the signed-in account once per drain and then sent
that account's captures until it ran out, whoever signed in meanwhile. A
capture that makes its strategy then made it for the new account (the
create carries no account), and the old account's strategy read as not
found by the new one, so its captures were marked deleted.

A drain now stops at the next capture once the account changes, checks
again right before a strategy is created, and takes no refusal or not
found that arrives after the change as a verdict on the capture: it waits
for its own account. A lost answer is still noted as possibly landed.