Calculate time spent in transition and eliminate the time in waiting for customer

Yes, you are correct. Measure days in transition status in a tuple with time default member will pull in the total time spent on the status Waiting for customer.

You can consider using the function Previousperiods to get time spent on Waiting for customer till the issue was submitted.

Please note. The measure might give you slightly incorrect data if you have additional status move to and from status waiting for custom on the same day when you submitted and issue after the submission. It is not the case for your particular issue, though.

DateDiffDays(
  [Measures].[Issue created date],
  ([Measures].[Transition to status first date],
  [Transition Status].[Resolved],
  [Time].CurrentHierarchy.DefaultMember)
)
-
Sum(PreviousPeriods(
  [Time].CurrentHierarchy.Levels('Day').DateMember(
    ([Measures].[Transition to status first date],
    [Transition Status].[Submitted to R&D],
    [Time].CurrentHierarchy.DefaultMember)
  ).NextMember
),
([Measures].[Days in transition status],
 [Transition Status].[Waiting for customer]))

The formula above might work slow for many issues. You can consider using some JavaScript calculation to get either this date or the days from issue creation till the first submission.

While we do not have an exact example with JavaScript, you can check these two posts:

Daina / support@eazybi.com