I fished upper k lake couple times since the ice came off. Fishing was great during first couple weeks after ice off, fish seem to hold nearby where water enter the lake. I caught more bull trout than cuttie this year in upper k. As for now... fishing will be tough as water is much higher and fish are more spread out. I prefer fish smaller hike in lake this time of year, there are many to choose from within kananaskis to banff.
Late fall is good fishing on upper k lake, but you will need a boat/motor to go around the lake to find fish.
Wedge pond is tough to fish without a boat, seems like these graylings are much smarter compares to the ones in bear pond. I dont know what's the size in wedge pond this year (got skunked last time fishing from the shore), but I think they are generally bigger than bear pond. I have caught grayling from wedge pond ~18" couple years ago before it got winterkilled.