Hi Jonas

I've not looked at your program yet through lack of time...

If you want to store in EEPROM, then the best and easiest is to save in the same (BCD) format as you are reading from the RTC. That way, you will remember that all operations, be they EEPROM or RTC are always in the same format.

Only convert to a human readable format when you want interaction by a human (ie Display or Setting).

Now, if you are saving to EEPROM, this raises another question - how often are you saving? Always remember that some EEPROMs only have a 100,000 WRITE lifetime... if you are saving every second, it won't be that long before you reach that limit.