New brake pads AND discs for the rear - needed?( 56 plate)

According to the service record from the original owner, my wife’s A3 54reg 2.0TDi DSG had new rear pads at 51,000miles, but not discs.

Now, 5 years later and with mileage approaching 100,000, I’m thinking of replacing the rear discs for what I assume will be the first time, as well as pads. Neither discs nor pads are near the limit, but I worry about separation of the friction material on old pads, and the discs are looking a bit scabby (though they’ve passed the MoT).

So my take on your question would be that a lip on the edge of the disc is to be expected and is normal, and probably the discs don’t need replacing, but a thickness check as suggested by portovechios would be a good idea. If they’re the same as mine, the new thickness is 10mm and the allowable minimum is 8mm.