Numbering sequences: identifiers people can read — When the number is handed out

Two choices. On create stamps the number the moment the record exists. On transition waits until the record reaches a particular lifecycle state. Where a lifecycle exists, on transition is the recommended setting. Allocating on creation means every abandoned draft burns a number, and a sequence full of holes reads as broken to everyone who sees it — even though it is working exactly as designed. Counters can reset yearly, monthly or never, and are advanced atomically, so two records created at the same instant cannot collide.