Couple of things to think about: SD NR licenses are not that tough to get here but its a consideration.
The bigger factor, to me, is the possibility of missing the migration. We are not that predictable on the migration. The pheasants will be here but the ducks can be gone prior to pheasant season opening. You plan a huge trip with all that comes along, and you've missed it. So I would not try to combo here. I think you can combo on the north end of the flyway, although I don't know what their upland seasons look like. I think you can combo further south on the flyway because I don't think they freeze up like we can and frequently do.
Id suggest doing the homework to make sure that seasons are open AND the birds you seek to hunt will likely be in the neighborhood at the same time. Just doesn't always work that way here in SD.
