In my younger years I used to go up to the Babine every year with my dad .... we would leave the 2nd week in October and be there till the end of the month. We would first fish tribs on the Nass, then a private stretch of river (only accesible through a farmer friend) on the Bulkley. Last we would fish the Babine ...... what a thrill!! Still my favorite river by far.
The best Steelhead fishing is usually from September until mid or late November. The lodge up there closes mid November. If you are going up there in the Spring (May, June, July) I wouldn't get my hopes up for Steelhead ....... but the Rainbow and Cutthroat trout fishing would be awesome. They would be there in abundance chasing the small steelhead fry.
Big hard fighting northern fish ...... check your regs ....... even back then there was a bait ban. I haven't looked it up but I would think that may still be the case.
For Steelhead you need to go September, October, or November otherwise you'll be disappointed. You'd be better off to stay here and fish the Vedder.