Does a flight number change require reticketing?
 

I have an Aeroplan award which includes UA segment. UA keeps changing flight numbers, and I called Aeroplan after UA changed flight numbers on YVR-SFO flight 5 (FIVE) times, and Aeroplan reissued the ticket.

Now, UA changed the YVR-SFO flight number once more (sixth time). Time or equipment did not change, just flight number. Should I call Aeroplan again to clean it up? Is it a simple revalidation, or is reticketing actually required?

I would call and clean up the booking to reflect the latest info, especially flight number change. I actually think time and equipment is less important in comparison.