Default version when source for not-versioned module
I noticed that when a target module of a formula does not have versions but source module does, a Forecast version (the one marked as current) is always picked up by the formula by default (merged with Actual), no matter how many further versions exist in the model. Is it a default behaviour that I can rely on?
I know that I can select a version in a formula using [SELECT: VERSIONS.name_of_version] but I'm asking about default behaviour, without version being selected in a formula.
Re: Default version when source for not-versioned module
Your understanding is correct. Please refer below link for more details.
The Currentversion is used as the default version for a formula where the source line item has versions applied but the result does not. Optionally, you can set the formula scope to apply to the Currentversion only.