Due to NW scheduling changes, I called NWA to reschedule me on an earlier flight connecting through DTW, rather than IND - same day, same end points.

Does the e-ticket need to be re-issued? (it's now 6h later and it has not been yet -- the trip is a week away)

Will this effect the automatic upgrade process on day 6 (or 5)? Does the upgrade process care if the ticket is re-issued?