Hi Steve
Tarfside Camping field is a community field. It is open to the public at least through the summer. Presumably the aim is to reduce wild camping and potential litter. As I recall the wording on the gate reads something like, 'The estate has no objection to the field being used for responsible camping'.
I have camped there during the summer a few times over the years. The last time there must have been about 3 or 4 tents in the area, although many larger tents tend to spread out over the wider area and have BBQs or camp fires.
Toilets close about 7pm and open about 7am.

I would warn you that with the tents and food regularly laying around, rats do visit the tents at night. Last time there a block of cooking butter was left outside and in the morning it was well marked with rodent teeth.

It's a nice spot to camp, and I've never heard of any problems.
Hopefully it will be open again by September.

Coli

Thanks for the reply Colin