Sorry, I don't think you started soon enough to have transplant ready plants for Mar 16, which is about three weeks from now.
Peppers take about a week to germinate with bottom heat, longer without. Tomatoes a few days less. As soon as they sprout, they open up the first set of leaves, called cotyledons or seed leaves, which look different from the regular ones. It takes a couple weeks or so after that for them to start opening up the first set of true leaves (again a little less for tomatoes and maybe a little more for peppers) and that is a process that takes a week or so to complete. I do not consider seedlings with one set of true leaves transplant ready - they are still very tiny and vulnerable.
I planted pepper seeds the first of february and tomato seeds yesterday, with the aim of having good sized transplants ready April 15 or a little after. My peppers are working on their true leaves now, but the first true leaves aren't full sized yet.
OK -- I read back through your post. I guess by transplant you didn't mean put them in the ground, since Mar 16 in PA would be way too early for that. So by transplant, you meant put them in to a pot? OR? If you mean putting them in a pot, it would be a bit earlier than I would like to do that, but probably they will be OK, if well cared for and transported gently.