I recently had my oil low warning light pop up, the oil was 1/3 between the min and max. I topped up around 750ml and now the oil is 1/3 above max. Should I be concerned?.
If your oil level is above 1/3rd when cold on a level surface that is way too much oil added and can lead to engine damage, drain/syphon the excess asap. This is true even for heavy oil consumption. I assume when you state 1/3rd that is looking at the same distance on the dipstick between low and max as a measurement.
You have only had the car for a month, check your oil once every week over a month, always with the same method cold or hot (after resting for 15-30 minutes) on a level surface. Some engines due possibly to incorrect break in procedure will have not properly bedded in piston rings and this is can lead to high oil consumption. High oil consumption according to Audi is less than 700 miles a litre, which is a crock of ----.
Personally, on a brand new engine I break the engine in with this method .....after pick up of new car. The next day I get the engine oil temp up to operating temperature (about 100 celsius on an S3) and find a quiet road put car in second gear and then from 2,000 with full acceleration to about 5,700 and then coast down to 1ooo rpm and repeat this two more times. In auto trans cars use manual mode and engage second gear and do the same.
This sounds scary, but it is not, if done on an engine at operating temperature. The piston rings will now be bedded. My 2017 S3 uses little to no oil after 2 yearly oil changes. Never below 8 tenths of max mark.
The biggest issue with break in and afterwards is using full welly on a dead cold engine, especially in the winter time. My car can take up to 10-15 minutes to reach oil operating temperature in the dead of winter.