You would like to use brackets around the measure and transition status to make it work as a tuple. The tuple, in this case, will give you a date of the last transition to the specified status. You might as well consider including time default member there:
([Measures].[Transition from status last date],
[Transition Status].[Status A],
[Time].CurrentHierarchy.DefaultMember)
If there are no brackets, eazyBI will use measure [Measures].[Transition from status last date] only. eazyBI uses the first full working formula. In this case, the measure [Measures].[Transition from status last date] is a fully functioning formula in itself. Therefore, it works, and the transition status is ignored. If you wrap it in brackets, then the fully working formula will be a tuple - a combination of a measure and members.
Daina / support@eazybi.com