This topic is sad reading for all professional pilots. It is unfortunate that it is an employers market at the moment.
I believe that any time on standby is duty time according to CAP 371 and probably the Company Ops Manual and approved FTL scheme. If you do not pay the crews they never appear as being on duty and then duty is not recorded in the FTL scheme.
IMHO it is your licence, take care because if there is ever an incident which may be nothing to do with you, you will take the rap and the company will exit stage left just as fast as they taxy the jets.
Get the hours and get out!