Originally Posted by Calchas

Often but not always.

e-ticket re-issuance/re-validation at BA is done by the back office, by some sort of manual process. Why is not known to us.

The ticketing queue is prioritized by travel date, not by request time. Therefore a ticket starting in December will not be near the top of the queue.

If the ticket pertains to reservations on other airlines the re-issuance is prioritized.