Its quite simple.
Did mine straight after they announced the changes as opposed to joining the rat race of throwing money at hour building to get a CAA CPL or ATPL. After all what's the point of having an ATPL when you just fly C150s !!! You will still end up with a JAR licence at the end of the day.
5 dual hours training on a complex type aircraft like an arrow. Then a simple general handling flight test - nothing difficult but to CPL standard.
You will need a CPL examiner (But not necessarily theough the CAA). They charge 150 pounds as a test fee.
For night instructor - 1 hour dual training at night and I think 5 hours ground school -> maybe slightly more.
Regards