I also think that there's no egg withdrawal for permethrin, when it's used as directed on the label. Rules change though, but I didn't see anything different this weekend when searching. You could call your state poultry expert (at the university) for the latest, or call the drug manufacturer.
Ivermectin will be in the eggs for a while and is not approved for use in poultry for that reason. You have to decide when to eat those eggs; I wait a week, for no really good reason, except it makes me feel better about it. Individuals who truly have adverse reactions to ivermectin (there are some) should avoid those eggs much longer.
If you look at the FARAD website, the topical use in cattle, which is approved, has these withdrawal periods; For meat, 48 days, and for milk, 53 days. LONG! It's a great drug, but it does linger. Mary