This looks like an urgent personal matter.
I would like to think, given the choice, they'd stick with the better (but clearly less lucrative) tour.. but the situation doesn't really appear to be about that choice. It's just bad timing.
Onto an unrelated matter, the most disappointing thing about letlive is their tour choices. They seem to be a legit band that wants to be taken seriously, but then they'll go out on a tour with Falling in Reverse. It gives you a (good) reason to question them. Thankfully (and confusingly), they also get on quality tours like ETID/TC and Underoath/mwY/ACB.
I think they just really enjoy touring. It seems to me they always take the next available tour as soon as they finish one