I don't see why not as long as it's dry, my workbench has moved quite a bit over the years anyway and have had to re-plane it flat 4 times since 2016, finally seems to be staying dead flat for good now.
thanks chaps. I'm getting readings of 10-13% on my moisture meter - is this on the borderline?
it was all just rough sawn stuff. I'm planing it up now. seems to plane ok actually
I've sawn and scrub planed up 5 sections now and have sealed the end grain with the best I had available which was bituminous paint