The wheel speed sensor / ABS rings on both rear wheel hubs have deteriorated and need replacing, I cleaned the magnetic ring on the hubs which worked for about 2 months but now the error has returned and I was lucky to get away with that since they didn't look in great shape. So, I'm now trying to get the right wheel hubs and everywhere has different inner bore diameters listed.

It looks like 30mm and 32mm are the two most common inner bore diameters, with 29mm appearing in some of my research; how can I tell what our A3 8P needs before I take everything apart?

Full car spec is an Audi A3 8P 2.0 TFSI 3 Door

MOT next month too! :O