I see no one has replied. I guess I'll give it a try. You obviously want to pump as close to every 3 hours as possible. However, it that's not the case, you want to pump as soon as possible after you are done travelling and then keep on your regular schedule. I don't think you will get engorged, but I actually had more problems with my earlier attempts at adoptive breastfeeding when I barely made anything. I was less consistent with the pumping and had a few sore areas back then.
You can try to hand express while you are travelling. Excuse yourself to the restroom and express the drops into a wad of toilet paper. It's not the same, but I think it must help some.
Congrats on the birth of your daughter!
Nancy