My RV8 was born in Germany, and the paperwork shows how strictly it was treated, it’s all “as a certified aircraft”. Power plant and prop all from a damaged certified machine. Maintenance all by part 145 organisation.
it was imported to Denmark and it took a year before it flew again. But it did. A few modifications were made, and clearly danish register is more liberal. It was still maintained part 145 org.
then I brought it to the UK. A year ago. And it’s at the final stage and should get permission for test flying paperwork soon if all goes to plan.
so: a year seems to be the answer!