cmos/BIOS Battery change/Password

I'm not a 970 Extreme3 user but all motherboards I've ever had, ASRock or other brands, do not require password to change CMOS battery so you shouldn't be worried.

Other point is the possibility to use a password to protect BIOS/UEFI settings not decided by you the owner/admin, perfect for systems/PCs used by multiple people. I don't know if after replacing battery the board will continue to request the password, but it must have been previously entered by you. If not, you can replace the battery without problems.

if you haven't entered BIOS in 9 years it means you're lucky, everything works as expected

As long as it works IMO there is no need to replace anything. I love anything that works well for a long time. It looks like you have a good board

Yes, random time changes is a symptom of dead CMOS battery.

You should not worry, if the battery is dead and you can use your PC normally means that you do not have important settings in BIOS, 9 years prove it. Simply unplug the power cord, press the power button to discharge residual power, open the cover and replace the battery with a new identical one. Easy!

Thanks for the good news!

I wish you many years with your 970 Extreme3 running well, healthy and learning