Hard to say as the shelf life is about 2-3 years for the AC stains. Check to see if it is 100% fluid, without any clumping or skinning of the stain.

Let it fully cure and dry out. It should be fine.

I did respond to you: "Both are excellent, with neither better than the other. Do you prefer oil- or water-based? Do you prefer damp wood application?...

After sanding, yes.

It doesnt really say, but it does look more like a paint than a solid stain. Sand off as much as you can then use a solid-color deck stain in gray aft...

Both are excellent, with neither better than the other. Do you prefer oil- or water-based? Do you prefer damp wood application?

Is that paint or a solid color stain? You do not need to remove all of the old solid stain (just what is loose and peeling) if you plan on going with ...

TWP can take rain for about 12-24 hours after application, as long as it is not severely overapplied. Prewet and rinse the railings while working. You...

Need pics for prep help.

Yes, you will need to strip and brighten for the old stain. Clean and brighten the new wood.

See this about new wood.br /> When ready, clean and brighten all wood for the prep and then stain. Stain options are on the link above.

Add pics for prep help.

What is on the wood now is clearly opaque, so yes, you will need a solid stain. As for prep, see this article:

Most of the old stain is gone, so no need to strip. Clean and brighten for prep while pressure washing: For the stain, look at the Armstrong Clar...

No, you have to strip. Plus, what is on your railings looks fully opaque, not semi-trans or semi-solid. You would need to strip the paint here unless ...