stripping problem

Hi, new to this website wish i would have found it sooner. In the process of restaining my cedar porch. I've gone along with the suggestion of this site and ordered 5 gal of TWP 100 and bought the Restore a Deck stripper and brightener. Problem is the stripper didn't seem to work all that well. The porch is north facing doesnt get any sun for the most part. I now think the old stain (7yrs) was the behr . Which reading on this site is the reason why it won't come off. Anyway i used all the stripper the best i could and am now in the process of sanding the porch. The problem is the sanded boards look alright for the most part but they almost look like clean green treated wood, with the spots where stain remained that i sanded looking like new cedar wood. There's also some areas on th steps that still look dirty. My question do i need to run a cleaner over it again before using the Restore a Deck brightener or will that take care of the problem alone. And if i need a cleaner what brand would you suggest that i can go out and buy thats readily available. I don' t have time to order some my daughters gradution party is in 9 days I'm under the gun here. Hopefully someone can give me an idea quick Thanks