I am then scheduled for a hotel pick up of 11:45 the day after I land for another Europe to US flight.
15:20 added to 21:50 would be a 12:10 report (my actual report time at the airport is 12:15)...so......
The rest period away from base includes a nominal 30 minutes travelling time in each direction from/to the airport so your operator has it spot on.
Not exactly clever though, 5 minutes over scheduled on day 1 leads to a 10 minute delay on day 2, 1 hour on day 1 = 2 hours on day 2 etc.