Thes are deep in the wood. Possibly oil, grease etc. They will not come out.

Stripping is much easier and better for the stain as well. Sanding can create issues.

Thank you for your response and I will do as you recommend. Out of curiosity though, why do you recommend a stripper versus using an upright deck san...

TWP is much better than SD. use a deck stain stripper than brightener:

What do you mean by strip? Sanding or using a chemical stripper product? Also, TWP101 versus Sherwin Williams product?

Strip and brighten is much easier. Do this for prep.

Yes.

@administrator I have not, do you think it is worth a try?

Not sure. Have you tried a stripper and brightener?

Use the Cleaner and Brightener Kit for the prep. No need to use a stripper. Probably two light coats.

@micah As long as you remove all of the current stain it does not matter.