This is what I was thinking too. It is so stuck it will take a couple hours to get it all off, but at least I can test with it.
One thing that worries me is that I had so many successful prints with exactly the same settings and filament I don’t know how it got this bad. I’m hoping I can prevent the same mistakes next time so I don’t ruin another surface.
Just for reference, what sort of plate did you replace it with? I’m waiting on a Creality glass PEI plate that should be here soon and I’m hoping it will be better. Still not sure how this happened in the first place but from what I read it looks like the print head was too close to the plate and it ground PLA into the bed. I was using the same settings as always and I trammed and levelled before my first print. It seems to have done this every time I tried to print this particular object— Is it possible the actual gcode from Cura could cause this?