I've got it permanently in standby.
According to the description from iRex, after some time in standby (1 hour?), it shuts off.
Still, after roundabout 4 days, battery right now was entirely discharged, without any usage at all. Can't be normal or can it? My Kindles "survive" weeks switched off. So either it doesn't switch off but remains in standby. Or it still runs dry even when switched off.
Same happened to me with BeBook Neo about a week ago (*), whereas nook for example still shows more than 60% battery. And I always charge them at the very same time for the very same duration.
(*) Can it be the WACOM tablets? Maybe they DO consume significant amounts of energy? I remember, tablets some years ago had been in permanent active mode, when the stylus hadn't been inserted.
EDIT: Poll about the standby time users experience:
https://www.mobileread.com/forums/showthread.php?t=76866