Pf8d that is good information.
Do you know if Atlas is treating Stanstead England like “home basing”, where a pilot has a ticket from the US to Stanstead and flies a trip onward with layovers provided by the company?
Otherwise I’m not sure an American would (easily) be allowed to work/reside in England, or could afford to be on reserve there while buying their own lodging.
Any expanded information would be great, and thanks for what you’ve already provided.