Come on an ASR is useless to change pairings.
The only way is a Fatique report followed by a visit to the clinic. Facts from the Safety department.
The only reason why the 201 on the the 340 with 3 pilots was not changed was because no one did fatique report but only ASRīs.
900 hours...... hey we are factoring so who cares.
Call "not rested" for the sim and if you are rostered over 900 hours....Easy!!! Hey but lots of pilots would like to make a few extra AEDīs and go over the 900.
Cheers