One of the problems with polymer plates is that they can be susceptible to scratches, if not handled properly. I must have picked up the smallest speck of grit when I inked this plate, because once I started to wipe it, these horizontal and vertical lines appeared, and they hadn’t been on the previous five prints I’d pulled earlier.
In situations like this, there’s nothing you can do except go back and make a new plate. Fortunately, because I keep very detailed notes, the second plate ended up being practically identical to the first and I picked up an hour later where I’d left off. It’s not always this simple, believe me.