Ansys Employee
The particles and flow will always have the same time so it injects on top of the new time step so that at its ends particle and flow have same time elapsed. I need to think more about the first injection time and I will comment once I can have time.
If you use unsteady file injection you can tell Fluent to start injecting from the column 13. I will recommend first testing with that file injection but adding some lines for other time events instead of repeat interval.