I was trying to change my return flights online between YEG and DEN and these options popped up:

Weird UA code shares from Edmonton to Denver:

United 5636
Operated by SHANGHAI AIRLINES
Canadair CRJ-200
Show flight details View seats
YEG 07:52 AM DEN 10:39 AM

United 5385
Operated by LACSA
Canadair CRJ-200
Show flight details View seats
YEG 12:24 PM DEN 03:06 PM

United 5590
Operated by HAWAIIAN AIRLINES
Canadair CRJ-700
Show flight details View seats
YEG 03:29 PM DEN 06:14 PM

Now the question of the day is: Will my upgrades clear?

(Actually, I gave up and called. The 1K agent did not offer any of those options.)