You need 100 hrs P1 and 200 hrs TT for CPL issue.
The CPL course is 25 hours therefore you effectively need 175 hours TT before your CPL course.
If you do the CPL and IR together, you can apply for both licences after completing the IR. These two courses take 80 hours and it means that in theory you could have 140 hours or even less TT before starting the CPL, assuming you completed your PPL quickly. Some schools might not like this lack of experience though.
45 hrs PPL including 10 hours P1
90 hours P1 hour building = 135 hours TT
5 hours night rating = 140 hours TT
25 hours CPL + 55 hours IR = 220 hours TT
Result, CPL/IR, 220 hours TT, 100 hours P1
All the above refers to the modular route of course. The course lengths are the absolute legal minimum required.
Don't know where 150 hours comes from. The only 150 hour requirement I know of is that PPL's who wish to be instructors (ie. not being paid) need 150 hours P1 to start an instructors rating.
[This message has been edited by foghorn (edited 06 March 2001).]