When he is a USC he can file for his wife and an immedite visa will be available to her. Sounds like he has about one year. He can go ahead and file the I-130 now so that it will be approved. He can then file the I-485 and get the category changed once he is a USC. This will speed up the process.
However long it takes for either him to become a US citizen, or for the petition's priority date to become current.
The movement of priority dates cannot be predicted.
For the latest visa bulletin see http://www.engnishimura.com/priority-dates/current
J Charles Ferrari
Eng & Nishimura
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