When to employ my lvl4

Stupid question, but what time and day should I hire my lvl4 staff and facilites, but avoid paying their weekly costs?
They arrived today, but i've not accepted them yet as im sure there is a way of getting around paying their wages/costs but still getting the benefit of the first weeks training. Any ideas?

Only time that can happen is after wages but before training (12:01am - 9:15am on a Tuesday)

Ta very much