Significance of preapproval, biometrics, final approval etc

I was wondering if getting to any of the stages of the process–preapproval, biometrics, final approval–prior to actually getting the card in hand have any legal significance?

For example, would we be legally allowed to go in and out of the country at any of these points prior to actually getting the residence card in hand? What about working or access to public services like medical?

I ask because I am trying to sign up for language course and they said we need to have done biometrics. Is there any magic to having hit that stage and not before?

OK, from what I know legally you’d have full rights to be ‘present’ in Portugal and access any public services in you applied before 1 Jan 2022.
There is a legal document called Despacho on this subject that I quoted many times on this forum.

In practice though, people who applied later still are able to live happily in Portugal with no significant trouble. I can only surmise that any significance possibly ascribed to the biometrics may stem from the fact that you receive a piece of paper from SEF/AIMA confirming your application. At any previous stage you only have a screenshot from the online portal.
Personally I was able to convince some public services to ‘serve’ me even with that screenshot. But it takes some persuasion effort.