Can I have the requirement cover depending on the release assigned ?

Soazig Verré
Hi,
I explain what I want to do :
I've got a product to test. I must test with several releases (Alpha release, Beta release). I use different types of test case in each release, so I plan my work like this :
Alpha Release => Req A, B, C - exploratory test case
Beta Release => Req A, B, C - black box test case
I need to check the coverage requirements for the alpha release, in order to reach a specific cover requirements, before use the Beta release. So I want to do that :
1- creation of Alpha Release
2- creation of req A, B, C, assigned to the Alpha release
3- creation of exploratory test case, assigned to the req A, B, C and the alpha release => the coverage requirements shows all the req are covered (but not run) for alpha release
4- execution of the test case => the coverage requirements shows all the req are run (pass or fail or caution or blocked) for alpha release
5- Assign the req A, B, C to the Beta release => I would like the coverage requirements shows all the req are not covered for Beta release. But Spiratest keeps the coverage requirements from alpha release
6- creation of the test case assigned to the req A, B, C and the beta release => the coverage requirements would show all the req are covered (but not run) for beta release
7- execution of the test case => the coverage requirements would show all the req are run (pass or fail or caution or blocked) for beta release

Is it possible to use Spiratest like I want ?

Thank

Best regards

Soazig