Sikkens stain in NJ ... options?

Hi -

Moved into this home in March of 2016, in New Jersey. The deck gets quite a bit of sun, I would say nearly full sun. I don't believe I am dealing with any mold/mildew issues, but a number of the deck boards are discolored and peeling. I clearly recall the previous homeowner telling me they used a stain from Sikkens -- only problem is I don't know which one. I also don't know the color exactly. I am attaching a few pictures here.

Question: Should I try to find the exact stain and just clean the deck and reapply same stain? If I can't figure out exactly which Sikkens stain/color this was, what are my options for applying a different stain... i.e., I would have to strip the old stain off completely? And if I end up stripping current stain, do I also need to sand?

Sorry for all of the questions, and appreciate your help!

Regards,

- Dave