Preseva Wood oil and sealer

I have a redwood deck that was stained with Preserva Wood Oil Stain and Sealer, Cedar color, about 6 years ago according to the previous owner. (I found the old can in the garage)  I finally got around to cleaning it yesterday with a cleaner and power washer (it was extremely dirty). I did the water test today and it appears to be no stain on the deck. But, there is all sorts of discoloration in the wood. Some areas look OK while others look darker. See the pictures. I'm trying to figure out if I need to use a stripper with brightener prior to re staining. Also, I know some of the wood looks a bit weathered. (we at 6000ft with snow all winter). I really don't want to sand it. Should I strip and power wash again? What type of stain should I use for the conditions?  Oh yes, we are about to get rain/snow in a few days, should I wait until spring to start again on the project?