Blueprint doesn't work when using "-" instead of "_"

when creating a blueprint the "create site" button grey's out as in the language code we are using "-" instead of "_".

Could you please have an enhancement to enable create site button even if we use "-" in the language copies.

Is this an OOTB functionality that was being used for Create Site command that was triggering for the payloads

msm:masterPages: /content/xxxxxxx/language-masters/en_us

msm:masterPages: /content/xxxxxxx/language-masters/es_mx 

But in our project specific we are using en-us and es-mx.

Now we can't go back and change the language to use "_" as that would need tremendous changes to our content system.