I fit both types, the filtered face-plates from a tech's pov are bit, fragile, in the way they fit. It's a slotted fitting. The pre 2018's at least have the 20mm screws holding everything together. I know another tech, he prefers to actually remove the plastic pushdowns inside and terminate straight onto the IDC type connection left behind. Yes the new ones look nicer and more streamline, but one flick of a vacuum cleaner and they release.
All you need to do Davyboy, is leave the cable that goes from the BT socket to the BT fiber box connected to the Faceplate, unplug it from the fiber box. Remove everything else pertaining to the old BB setup. On the back of the new router there will be ONE socket that is correct size for the RJ11 (router to bt) lead. Don't plug the router cable into one of the 4 (there's usually 4) network sockets on the back of the router. It will physically fit but you will see a Network socket is larger than the BB connection socket. That's all you have to do really.