I'm pretty sure the trout season doesn't finish until the 6th of oct in a lot of places, lochs especially. I know I have definitely fished several lochs north of Inverness(far) in the first week of oct and had some excellent sport. This time of year the loch trout can stack up at the mouth,s of inflow burns preparing for the spawning run. With the rain forecast tomorrow you could have excellent sport.
If you only have a few hours then do as mike said speak to the guys in the tackle shop, choose an area/ticket with a few loch,s as one could be switched off and then buy an ordinance survey map
Wish I was up there myself this weekend.
I would fish wet flies in teams of three, chop and change with the usual kates and bibio,s etc, try the bigger sizes and ones with flouro tails.