I have a 2006 Octavia Estate, and currently repairing a bit of rust to the lower side sill (under the doors) and noticed there is a type of tape that has been applied (possibly at factory) and I could do with replacing some of this where it is peeling away. Does anyone have any idea what kind of tape this is, or what I can replace it with?? Thanks.

It'll be the stone chip guard, mask and spray with a suitable substitute.