I took down the laminated plank that I will use for the deck beam.
I happily bounced up and down on it, not a worry.
It will take some planing, but apart from that it seems fine.
And the cling film / plastic wrap did indeed just peel right off.
Since I'm starting out on building a small sailing boat, I thought it might be useful for others to learn from my experience. This will be a log of the building project, and any problems and solutions along the way.