Seat Question

I have united premier silver status. I'm currently in a preferred seat but I'm usually a window seat person. No window seats in economy plus that recline are currently available BUT I can upgrade for free when I check in.

Do I keep my current seat which I currently have the whole row or do I pay for the aisle seat in economy plus? I have a feeling that the only two aisle seats won't be available when I check in so I'm willing bit the bullet but could probably sleep better if I had the whole row.