A little note to those advocating landing without getting prior permission.....
The aviation insurance legal advice we have received is - land WITHOUT prior permission,and you are no longer covered by insurance. This is for cases when Prior Permission is specifically required and that requirement is published in documents that you as PIC would reasonably be expected to have access to (like ERSA), . This is in the event of any damage of any type (that you sustain or cause) during the time from wheels on to wheels off.