2008 Cadillac STS - automatic time update

I recently had to replace the battery on my 2008 Cadillac STS. I was told by the service department at the dealer that they could not reset the date and clock. I was told that they received a memo from Cadillac that the date and time would automatically reset itself on August 16, 2020. Shall I believe this or file a complaint with the manufacturer?

I would ask to see the memo - call another Cadillac dealer - use the contact number in the manual .
Someone here may see your post but having the answer might be slim.
Also have you tried setting the date and time by your owners manual instruction .

Engineering is working on a fix for the automatic time update.

Service bulletin PIT5652D shows how to manually set the time
by entering the diagnostic mode in the display.

This keeps up the tradition of automobile clocks never working properly. The clocks on my parents’ cars that they owned back in the 1940s and 1950s never kept time accurately. The first thing we would do when they bought a used car with a clock is pull the fuse that disabled the clock. These clocks were spring driven and a solenoid would rewind the spring every two minutes.
The manual in the 1954 Buick had instructions for reconnecting the battery to be sure the clock would function properly:. “To be sure the clock is fully wound, turn off all lights and accessories. Strike the negative cable against the battery post. Then scratch the battery cable against the post. If there is a spark, allow the clock to run down and repeat process until there is no spark. This insures that the clock is fully wound”.
Isn’t it wonderful that 54 years later, GM still hasn’t figured out how to restore the clock function after replacing the battery?

I am asking this is all earnestness:
Do you REALLY think that any manufacturer is going to respond to a complaint regarding an 11 year old vehicle?