[baD]

I think there is enough cross-over to make a significant financial difference to clubs ending up racing at the same time on the same day of the week.

If Longbenton cannot find a venue for TCs on a day other than Sunday then inevitably a Sunday is better than not having a dedicated TC venue at all, but it is to be avoided if possible, imho.
The simplest example is if a club runs a one off competition, the other will likely have a poor attendance, as competitions tend to attract numbers.

As CP above said, the hope would be to keep the options open re racing on various days of the week. I'm sure he would like the chance of an off-road track on the odd Sunday when he got the chance.