...I often leave my Sky box recording unattended for a week at a time. From what you are saying this may produce issues...(in the Humax)
I left my Humax 1000S recording unattended and in standby for one month, it did not miss a single recording. I have settings of auto on/off and padding of 2 min start / 10 min end.
Having said that I am not 100% happy with the box which is liberally scattered with bugs and stupid omissions, due I think to design by committee with no single overseeing responsibility. Hopefully, given the level of dissatisfaction being openly expressed on the Freesat forum, this will get fixed.