At the moment, we only know of 1 place being available as Lee Probert stepped down at the start of the season.
We've not heard of any other retirements as of yet.
Three referees had trial games last season (Jones, England, Robinson) so there might be more than one promoted but I'd be very surprised if it was four.
I think Jones will be promoted and perhaps one other, unles there are multiple retirements we don't know about.