If you get six or more points on your licence within two years of passing your driving test your licence will be revoked.
Any penalty points you get on your provisional licence that haven't expired will be carried over to your full licence when you pass your test – points usually last for 3 years. However, your licence will be revoked if you get any further penalty points that take you up to a total of 6 or more within 2 years of passing your driving test.
If your licence is revoked, in order to be able to drive again, you'll have to apply and pay for a new provisional licence and pass both theory and practical parts of the driving test again to get your full licence back.
The 2 year probationary period only applies to the very first test you take, this will usually be for a car or motorcycle, it doesn't apply to any further tests.