It varies.

August I had three consecutive nights booked separately at an HI and got one set of pointe (plus breakfast)

in October I’d booked 4 consecutive nights separately and got 4 lots of welcome points (plus the breakfast)

this was the same HI

don’t know whether that was a glitch or the guy on reception trying to do something nice as there were no upgrades available.

im going to take that as a bonus and not complain about the first stay being different from the second!