A user may be invited to multiple tenancies and potentially be allocated a variety of subscription levels across these multiple tenancies.

However, the highest level of subscription that the user has access to will flow across for all their tenancies.

This means that if you purchased a Silver level subscription for yourself but are invited to a Team tenancy and given Gold level within that Team Tenancy, in reality your Team Gold access will actually flow across to all your Tenancies enabling you to have access to more features even within your Personal tenancy where you originally only had Silver.