When I applied at Cathay I was also a regional jet FO, also with zero turbine PIC. I did do the ATP at allATPs in order to apply to a different carrier. Fortunately for me, that carrier did not work out and Cathay called. Upgraded to Captain while I was waiting for a course date.

As always ask an accountant but that year I was able to write off the entire trip to get the ATP (hotel, meals, and the flying). And it was a piece of cake and had fun doing it.

Good luck.

FO