If I have an on-call shift and get called into work I get paid 1.5x base rate
I work12 hour shifts Monday, Tuesday, Wednesday of a week and on-call where I was called in on Sunday for the whole 12 hours.
My employer only paid me 12 hours overtime. I am in a union and am a union steward but am constantly fighting the other stewards due to their lack of wanting to do anything. Our contract states we be paid 1.5x for on-call.