We have been to the Port Police in the South/Paphos and made the enquiry as to sailing a yacht from the Nth to the Sth.
If you do not have a stamp in your passport but have a clearance certificate from Turkey
or Greek Island, you can then check into the Sth
So if your boat is in the North (TRNC) you have to check out and then check in at either a Greek Island or Turkey
and then you are free to sail to the South. BUT do not tell them that you have been to the North!
All above was told to us by the Port Police.