Merh - I did exactly what you want to do re CPL with Steve Pearce at PBAFT in Moorabbin in 1996.
After gaining the required hours in private flying my CPL 'training' consisted of 2 x CPL navs, a couple of hours IF to get minimum hours and then the CPL flight test. All done in less that a week.
If your current school is stuffing you around, talk to Steve at PBAFT.