Everything here is very speculative until more is revealed or known about the situation.
Personally, I don't buy the stepped down for health reasons or personal reasons as that would totally go against the 'Faithful and Discreet Slave' doctrine they have conjured up. If Christ has selected old Tony, then being closer to death means being closer to the heavenly reward as not just one of the 144,000 but of the specially chosen FDS (may be there are even two classes within the 144,000 lol).
On the other hand the FDS doctrine can be bent to show the FDS is a 'flexible' arrangement for dispensing 'spiritual food at the correct time' and therefore can be and is a much a body that changes regularly.