Question Author
received a reply, but still none the wiser how I can pay it!
We thank you for your clarification of the issue and can confirm all is now in order.
Regarding your query, due to the stipulation of your lease, your Ground Rent is not collected directly by ourselves but rather by an intermediary collector, as is often with these old leases, and whom in turn then pays us. As such, you do not receive the annual demands from ourselves. Changes of ownership, permissions for extensions etc though, must be addressed directly to us