It won’t come off if you use it correctly . Used it loads over the last few years.
Make some no loose bits on the screed. Prime it as well so better bond.
Was the chipboard all level ?
We tend to find chipboard is level as it’s new. So then we go 6mm ply and feather finish.
How did he screed the floor? With a trowel or a pin leveller.
Warm them up with a hairdresser the use a knife to get a corner up.
Hopefully the glue strength is less then the screed strength so the scredd stays down.
Cant use the 1st one. Thats for glue down. You need an expansion gap. Need the 2nd one. Look on stairs rods website.
https://stairrods.co.uk/ali-top-nose