I heard loud calling from multiple GGs and tracked it to the site of Baldy's previous failed hollow, where an unknown pair were sitting in the hollow entrance (last photo). A couple of other birds were flying round, and I recognised Baldy when he landed at a hollow in a nearby tree and started chewing around it. His partner, with her GPS tracker still in place, was sitting on another branch, but then joined him. They both looked inside the hollow at various times, but it didn't seem very deep. The other pair flew around a bit and all four birds continued to call loudly the whole time. John had seen the Baldys chewing around another hollow some distance away a couple of days earlier.