Creating an environment from the dev portal doesn't use the manifest default values

Hi Team,

As the parameters' default values of the ARM template I use in catalog are defined for a production environment, I set different default values in the manifest.yaml file.
However, when I create an environment from the dev portal it is using the default values of the ARM template instead of the ones defined in the manifest.

It is quite counterintuitive as it is not the values displayed in the dev portal during creation that are actually used.

Is it the expected behaviour? Is it possible to improve that behaviour as it would be very useful to be able to use different manifest files with the same ARM template for different environment type?