I've seen a few drake BWT shot in the first days of the season, and we had a pair of drakes come through the decoys on Sat morning that were definitely bluewings. I hunt a few spots that they seem to like to hang around in. It seems like they are mostly gone by the time the season starts and all gone by the second week of October or so. The BWT and Cinnamon hens are next to impossible to tell apart unless you have one of each in hand but I'd be willing to bet that if you shoot a hen it's a 95% chance that its a cinnie.
Avery- the K-Mart of waterfowl gear.