I think it's probably still worth turning up to the car park if you are there relatively early, the tournament attendees are likely to be there before general attendees and although there are 4 tournaments there's likely to be a lot of people getting to the event via means other than car
If you have no joy or want to avoid the parking charge, I'm pretty sure the that the residential areas around Ashton Gate east/ north-east are not permitted so you can park there, how much space is available on a Saturday/Sunday morning I'm not sure though.
If you want a guaranteed Plan B I would suggest Long Ashton Park and Ride, its about a mile west of the stadium...
Long Ashton P&R.JPG
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