Gang gang pair both in the hollow and doing some repairs; chewing at edge. They were alternately going into the hollow for a period of time , whilst the other basked in the sun at the hollow entrance. This hollow( and I think this same pair) has been successful in previous years with hatching and fledging a chick.
The sentinel - just love this girl..I have observed her over the pas 2 years and so happy they are back again. Her man was down in the hollow for a time whilst she sat sunbaking and grooming.