How do account for added resources after a task start?

[skipperjohn]

In short, I want to schedule a 315hr task with one resource at the start.
Midway through, I will have another resource available to assist with the
completion of the task. What steps do I need to follow for this to be
reflected in the schedule?

 

[Jim Aksel]

I would do it this way. Add the additional resource as you normally would.
Then, change to the Task Usage View on the View menu. Scroll down to the
task in question. On the right side of this view, you can manually adjust
hours for each resouces assigned to the task. What you will do is enter 0
for the periods where the second resource is not available. You will want to
be sure to watch how the total work changes since you want it to stay at 315
hrs.

If necessary, you may change the time scale by right clicking on it.

There is further discussion in the help sections under "Resouce Contouring"

An alternative way would be to establish an individual resource calendar for
the second person and block their availability appropriately. I personally
prefer the first method.