I would say they are inactive, semi-retired, or busy with other things. But, if and when they choose to come back, we don't want to surprise them - so we let the admin stay. Fact of the matter is that everyone is busy, and we are thankful and grateful for whatever little we get. What you say is right. There are 5 -6 active at any given time.
Sir, you yourself may login, and soon (not immediately, you can understand that) you may start helping out as admin.