If you do organise a weekday visit & want a lot (and I mean A LOT ) of information see if you can book a tour with Chris Wren, he could talk the hind legs off a whole field of donkeys about the BOB
I have been on several tours with Chris & talked to him many times & he is a walking encloypedia on the subject.
If you properly understand how the tote board works by your 2nd visit you're doing well
Bentley priory should be open or opening soon. I couldn't find any info whether it is open yet or not
we visited a couple of years ago when the renovation work was going on & it looked very promising.
http://www.bentleypriory.org/