My 2023 P4 has the same issue the a/c cycles between blowing cold and not so cold. I asked my main dealer about the issue and they checked that the pressure in the system was ok. It was. The explanation given I am told by MMC was that as the interior of a morgan does not have a thermometer attached to the system to switch the a/c on or off when the desired temp is reached the system is on a simple timer. This switches the cold a/c on and off in a cycle as we are all experiencing. I am also told MMC were asked if there was a fix, the reply being they would look at it! Surely the simple and easy fix would be for the compressor to be on when a/c switch pushed in and off when out?