I tried to keep track of the prices/increases early on, will post the figures I kept below.
What you had to pay for a 72 plate would have depended on when you placed the order.
These numbers are for a Sportback with no options above the trim line. I think Saloons are +£1k across the board.
Also, these are the base prices, you've got to add first year VED (It was ~£1350, but I think its now up to ~£1500), £715 OTR costs and £575 for any standard paint other than Kemora which was free.
Earliest numbers I have are these from mid November '21.
RS3: £48,840
Carbon Black: £53,490
Vorsprung: £56,090
Late Dec '21 was the biggest increase of £2930.
RS3: £51,770
Carbon Black: £56,420
Vorsprung: £59,020
In April '22 there was a £750 increase.
RS3: £52,520
Carbon Black: £57,170
Vorsprung: £59,770
I stopped keeping accurate track after this but there was another increase in Nov '22 of around £1,100 to average OTR price.