There are still many 'Wake me up over Windsor' CSDs out there who are clinging to those restrictive working practices drawn up in the 1967 BOAC Scheduling Agreement.
I have LITERALLY seen this..much to my chagrin. On the way back from SIN, CSD stood in the doorway greeting, but as soon as the aircraft was in the air, she came into the F cabin, took off her shoes, wrapped herself in a Blanket, fully uniformed and curled up in 5A! Remained there until lights out, then put out the bed, and got under the duvet. Stayed there until seat belt sign for landing came on, then got up and strapped into crew seat!
The purser was beside herself trying to cover the work and the fact that it was happening. Poor woman. Not sure what the rest of the F passengers made of it.