u/Animal-Crossing-1717

I got a seasonal job working in Alaska at the end of February based on the idea I could work from May till mid September. This Friday, the day I flew to Alaska, I was offered a full time job. I said yes to the full time job but it most likely won’t start for another month or two. I am now in Alaska doing the training for the company and I feel guilty. They are talking about plans for the whole summer. What should I do? The managers are really nice and I feel bad. I don’t even know when I officially start the other job and how do I even break it to them?