I am afraid it is true as I have had the documentation through from the CAA now. If you put a plane on the G Reg it must have its engine replaced (or overhauled) after a specified time or hours. The specified time in my case and most engines was 12 years but after that time it seems it can be used on a private use basis but on condition of a 100 hours engine inspection.
You can have a 20% time or hours extension and continue to use it for public use but only if it was previously on the G Reg for the last 200 hours before it expired. You can also appeal to the CAA against this and that is what I am currently doing. Hopefully the fact that my engine is only 600 hours old and had a top end overhaul 0 hours ago will see sense prevail.
It looks like there will be many planes making it back across the Atlantic before their time expires here.
Ironically I purchased this plane from Germany just before the engine was 12 years old. The owner was selling it because he didnt want to go to the expense of putting a new engine in as Germany have had the 12 year rule for some time I believe.