Thank you very much - unfortunately it wasn't as simple as I hoped, the diagnostics came back with a bunch of errors (including ABS!) so they're having to take the car to Audi to get it all checked out... A bit frustrating, but at least Audi Assist provides a courtesy car, which I didn't know, so I'll still be mobile 😃
2017 RS5, and had the dreaded brake servo and stop/start warning messages this afternoon...
Luckily my car has an extended warranty, so I've called Audi Assist, and someone is on their way - hopefully they'll be able to fit the sensor, and there will be no damage to my ABS! 🙏