I hope someone can help me!

I'm having my above ground pool liner replaced and purchased a new liner plus a bunch of supplies from a pool place. They threw in a liner shield (the shield that goes under the liner on the bottom of the pool). Of course now this is backordered and the liner guys are coming tomorrow to install my liner. Does anyone know if I should reschedule and wait until the shield comes in or is it really not necessary to use one?