Place two staff on each day in order, skipping blanks

I'm stumped and not sure this can even be done. I have this calendar with a total of 31 staff assigned. I need to assign two staff to cover each day not grayed out utilizing the staff tab from the top (A1) to the last (A31). Need to go to next name if blank.

Example:
Bob

Bill
James

Kathy

Should show
Bob
Bill

then
James
Kathy

not

Bob
Space

Bill
James

Thanks rcm, it works great

I didn't think it was possible but, that shows you it's never hurts to ask.
Again thanks.

You are welcome. Please mark it as solved