Two weeks, or 14 days from worming. You will want to do a follow-up worming 10 days after the initial (that only kills mature worms, you want to give the rest a chance to grow up and then wipe them out too) though, so that would be a total of 24 days.
Don't forget to dust for mites/lice and repeat at 7 days for mites, and again at 14 days for lice. They are very very common and if the seller killed the bugs for you right before selling you won't know until eggs hatch if there is a problem so best to dust preemptively. I use poultry dust (permethrin).
I toss eggs for 14 days after last dose. Don't forget to repeat wormer to break life cycle. It is off label as there is no wormer approved for egglaying hens so you have to do what you feel comfortable with.