Stop scootching forward.
Don't worry about the metal plate. If you are sitting on it, you'll know soon enough. Pre-emptive scootching lands you on your soft tissue.
If you were scootching forward because you needed to get over your pedals, I'd say move the saddle forward. But if you're scootching out of fear of the plate, like you say, then I'd just stop scootching and see what happens. The transition zone (if it fits) will stop you before you land on the plate.
"If Americans want to live the American Dream, they should go to Denmark." - Richard Wilkinson