Thanks for the reply - not sure it's relevant for us: we're three flying in from out of province/country without bikes (I guess we could rent?) and not all equally comfortable biking in mountains. Also we've already booked since as far as I can tell Parks isn't letting anyone on the road without a booking at the hostel/hut.
(For some reason I can't find the things I've posted and I don't get notifications if they are answered - any ideas how to fix this? eg I just saw this response by chance, and I posted another question at the same time about side trails off Tonquin valley and now I can't find it again to see if anyone else answered!)