If they are laying before you get them they often lay one egg, which will have been on the way before they moved before downing tools until they settle in. Changes in routine, enviroment, diet and establishing a new pecking order is as stressful for chickens as moving house or starting a new school can be for people. How long they take to get back in their stride can vary but I find moving POL birds more disruptive than established layers. POL is a description of their developmental stage and a bit like people the age that the become sexually reproductive can vary. some can take a few weeks longer than the others of the same type to get going. Its still quite early in the year yet, even some of my productive layers havent started laying again yet this year.
There is an old rule of thumb which says that laying birds stop on Bonfire night and start again on Valentines day. Not all of my girls observe this tradition but there is probably some truth in the fact that by mid Feb, the longer days are providing the required amount of daylight for hens to lay.
Buffy