I was looking into some mother & toddler groups. Never thought about a theatre group though.

Try and find a "Newcomer's Club" that way you will meet not just British Expats but Canadians and other nationals who are reasonably new to the area and obviously looking for friends. I love the one I joined in Ontario. Ours is very relaxed and good range of ages and nationalities.

thank you!

I don't have kids but in the year I lived in Edmonton, I made more friends there in that year then I have in 9 years in BC (Vancouver region). I really found most in Alberta far friendlier and open to new people, and personally I think Alberta is underrated because of the long winters, but I have always enjoyed the province and had no issues with Edmonton, offered everything one needs within a reasonable commute, decent roadway system.

We have 2 seasons in Alberta - Winter and construction (road works)

For another way to meet people try looking at meetup.com for groups in Edmonton and area. Alberta seems to be quite a transient Province with people coming in to make their money from the oil & gas industry then going back to wherever they came from to begin with. In general I have found it to be a friendly place, although I much prefer Calgary / South of Red Deer to being up in that part of the Province. There's nothing wrong with it, just I find it "feels" nicer down here.

Good luck with the move.