Yeah... that "sitting discharge" test is no joke with AGM.
I've had cheapo batteries last through the winter when I was renting and couldn't trickle charge, meanwhile my BMW's battery can barely start the bike after a week of drain and the last one bricked itself after an idle month. If we didn't buy a house I was ready to sell that stupid bike over the battery troubles.
Dropped a gear... . . . . . . . . . . ...still here