The peanut butter should be on both slices of bread forming an oil envelope around the jelly or jam. The peanut butter won't make the bread soggy, and will protect the bread until lunch time.
I actually have fond memories of the jelly soaked bread in my brown bag lunch as a child.
Yeah I liked my sandwiches smashed and soggy. On the occasions where I'm going to be dirt bagging for a week or so, I'll still take a whole loaf of bread and make it all into PBJs (and stuff them back in the bread bag) to eat throughout the week. It's usually in the winter so I'm not too worried about mold.