When I had a chat with them recently about calling them to say we were on one of the moorings that they are responsible for, a reason for boaters to call was so that they knew if or how much spare room was available at that particular mooring for others to use.
The person I spoke to was well aware of the boats I am associated with and knew we only ever moored overnight but still asked us to call in for the reason above.
Tesco Reading moorings - Please get in contact with Reading council to ask that the first 24 hours are free so that those who want to can use the Tescos without penalty.