Hi Ed
Wednesday afternoon is good.
I have played at TSB http://www.tsb-sportpark.de/tennis/
It's in near by Germany (accessible by public transport, bus 55)
One doesn't have to be a member in order to play and it's cheaper then in CH.
The pricing is 25€/h from 10-14h, or 29,50€/h from 14-17h and 37€/h form 17-22h
We could try 12-14h? If you want call & book go ahead..