Hello @Frank Towns
Unfortunately it is not possible to swap KeyVault CURRENT VERSION and OLDER VERSION.
Here is a workaround. You can disable CURRENT VERSION secret and create new version of the existing OLDER VERSION secret. Secret with OLDER VERSION secret value will become CURRENT VERSION
Also you can also implement KeyVault Secret rotation or use 2 separate KeyVaults without need to create a new version every time.
https://learn.microsoft.com/en-us/azure/key-vault/secrets/tutorial-rotation-dual?tabs=azure-cli