Hi Rozm2004
Yes, it is common for them to extend it twice as they have a backlog of cases.
Only you can decide whether you want to inform them of your worsening condition now. You can do this and inform them that you are doing so for informational purposes. Alternatively, you can wait until your next review, as many people who have an enhanced award do. Most people don't want to risk having an earlier review, so they keep quiet unless they are hoping to improve their award.
BIS
Nothing on this board constitutes legal advice - always consult a professional about specific problems