my new Audi A3 bought July 1st has covered just 1700miles and the dipstick now shows oil to be just half full

Hello Richard,

Many thanks for being in touch. I think you are going to find that the dealer will tell you that all new vehicles are expected to use some oil within their bedding in period, and some will claim this can extend until the car has covered some 3K miles or so. 
If it were mine, I would return to the dealer and ask them to top up the oil to the correct level, and ask them to record the quantity used against the mileage covered ( you would be wise to also keep a record of that). 
You can then continue to monitor the oil use, and hopefully you will find it will decrease. 
Kind regards,

Gareth. 

I agree with Gareth, get this booked in at main dealer as it's under warranty. That way if there is an oil consumption issue Audi try and get out of at least nyiu can show it's been in before.