In my experience the Display Format stays fine until I change to a different channel, and then it won't auto correct or if I go back to my SD, it defaults back to the format I did NOT select for it the first time I tuned to it. This has been the case for YEARS--and YEARS!
OK, I don't know if this helps, but I have found that when I am NOT able to affect the Display Format (most likely because I was tuned to an OTA channel when I set it), I have to tune to a SAT High-Def channel, and then I am allowed to change the Display Format, and then I can put the HD channel back to the proper Display Format, and then I allowed to change the SD channel to any Display Format I want. This has been the bug FOREVER!
At this point I would choose the EPG data for all the OTA sub-channel diginets over Dish fixing the STUIPID Display Option bug, but I should NOT have to choose, but expect Dish to fix BOTH!