It seems the Kents are winding things down in preparation for retiring except for the Duke accompanying HM for things like The Trooping. I have to think this has been in the works for awhile and just delayed until after Philip's death. I also find it interesting the Duchess of Gloucester has taken on some additional duties. I know she is a decade or so younger than the Duke and Princess Alexandra and I can see her being something of a bridge between the older and younger generations in terms of duties.
On a side note, that shade of green is gorgeous on Catherine and is so appropriate for Wimbledon.