Maybe an independent instructor would be better? I had a few with BSM a few years ago (were an xmas present - I was NOT happy lol) and I just felt like another in a long line of learners, iyswim - it just didnt feel right, wasnt personal etc Then obv I gave up again for a few years... this time round I had my lessons with a lovely woman who understood my nerves and even changed her times to start at 8am on sats instead of 9am so that a)it didnt matter if my dp had to work that day as he could start a bit later and therefor have our son while I had my lesson, and b)I wouldnt be worrying about my lesson all day - just get up and go!
Its definately worth finding that instructor that you just 'click' with, as you'll be spending a fair bit of time with them, and you cant learn if youre not comfortable. We phoned around until we were happy.
I think an hour a week is fine esp to begin with, my instructor said you dont want to 'peak' too soon anyway and you dont want to get driving overload and get farked off with the whole thing