Booked a 70 200 2.8IS in (Brisbane) with a 20D to get looked at regarding focusing issues. They had to ship it off to Sydney I think.. Came back good in a couple of weeks (got them to send it back to me). Happy with service.
On another occasion had to send the 20D in with grip to get the grip (1st gen) fixed. Was a bit annoyed I had to send the camera in as well, but had it back in a couple of weeks too. Good experiences so far.
I guess depending what the problem is, the time taken will differ. Busted zoom mechanism.. I wouldn't like to speculate, but I think you'd have to be quite lucky to get it back mid-June. Good luck though.