Add new resource in a long running task


There is a Task A which has an estimate of 6 weeks. There are two resources who will work on this task, Resource A and Resource B, both have a utilization of 70%. Task A needs to start on 04/19. Resource A is available from 04/19 and resource B is available on 04/30.

Actual behavior

When I add this information in the project plan, I am not able to start Task A on 04/19. It starts when resource B is available, which is 04/30.

Expected behavior

I should be able to allocate resources to the task. Omniplan should be able to provide an expected completion date with the above constraints.

Things I have tried

  1. Task splitting : I tried splitting task A into two sub task but ran into the following issues:
    1. It seems I cannot split the task into two if their end and start dates coincide.
    2. Since the resources are working with 70% efficiency, I cannot simply split the task into 8 days and 4 weeks 2 days because in 8 days, resource A will only be able to finish 5.6 days worth of task (8 * 0.7). Although I can do this calculation, I hope Omniplan can do that for me.
  2. Resource leveling with split option: This didn’t change anything.