One thing to try, if you're available, since it's 100% consistent for you:
1. Make a new save
2. Sleep through a single day
3. Go back to the main menu, and head to the load game screen
4. Check that it's indeed Day 2 of Spring, Year 1
5. Try to delete the save, and go back to the main menu
6. Go back to the load game screen
If the save is still there after that, what date does it report?
Day 1 of Spring, Year 1
or
Day 2 of Spring, Year 1
I'm suspecting it could be an issue with the save auto recovery feature that was added prior to the 1.6 launch on console/mobile, so this info would be helpful to check
Thanks for the patience y'all, and I'm sorry this issue is taking so unexpectedly long to fix.