Just finished sanding my deck. Did I remove enough of the stain?

Unfortunately, I found this amazing website too late.

I have a 6 year old deck and applied one coat of Behr Semi-Trans Cedar after 9 months of weathering. It failed last year so I power washed the deck with Behr All-In-One Cleaner and then sanded the remaining stain off with 60 and then 80 grit. Belt sander on floor and used a mouse on everything else. It took a lot of sanding to remove the stain (still not quite finished) and now I’m concerned I over sanded. The deck is damp in the pic so a little darker than when fully dry.

What’s my next step? Should I apply a brightener and stain immediately? Sadly, I bought Behr stain again but will be donating it after reading this site! Debating between oil and water based stain now.

I still also need to refinish my front porch which is shady and suffers from black mold. What’s the best process here? RAD/sand/stain?

Thank you!