I am looking into getting my full licence soon, i have a full car driving licence.

First of all, CBT asap.

because im only 20 i will have to do a restricted access course (£280) which will let me ride a bike with no engine size restrictions but it will be restricted to 33bhp.
Get a bike and get it restricted to this, 21'st birthday comes will it be then possible to take a "test" (£90) on an unrestricted bike and take my restricter off? or will i have to do a full direct acess course?

would it be better to wait till april and im 21? or is this a cheaper alternative?

sam