You are right to be concerned.
Many sex links do enter POL very early. 16 weeks is not unheard of for many of these hybrid strains. Learning to lay in the nests provided is a bit of a learned behavior. If there are older hens to teach the younger pullets, sort of monkey see, monkey do, kind of thing, there's less concern.
I'll just share what I do and you can apply it as you see best. I prefer NOT to free range POL pullets. I keep them yarded at this critical juncture. I'm just not going to do easter egg hunts. I've enough to do, plus, there are far too many places for hiding. By a couple of weeks of working out their habits and their fixating on the proper nest provided, I begin to allow them to range in the late afternoon and evening, as 99% of them will not lay after 4 pm. This still provides them 5 hours of free time, but reduces the laying off site issue to virtually a zero factor. Hope that helps.