We keep an umberella cockatoo for about 2-1/2 years now and have found that they need to be kept occupied with toys and things in there cage to keep their attention, we leave the tv on for him when we are gone, Dont know if this does anything for him or not? Buy more important is a schedule.
If work schedules change then so does his time out with us and he does not handle the change very well at first usually takes a couple of weeks for him to accept the changes.
He also gets check ups at the vets every 6 months and at the same time gets his wings clipped and nails trimmed.
It is important for the vet to do these, as it is very traumatizing for the bird and is better he hate the vet then you. LOL