Their hormones and length of daylight and stress level after the move can all impact egg laying. The only thing you can do is to make their move as smooth as possible. Make sure they have fresh food and clean water. If you can give them the same food they are used to at their current home it may help. Make sure they have a dark secluded place to lay when they are ready. It could take awhile before they lay, moving birds can really disrupt things. Even if you don't see an egg for another month I wouldn't worry too much.