If they truly believe what they claim, he would most likely step down for some other reason, and quietly leave, or maybe stay on as a non active GB member in name only, so as not to have to explain it!!
I know two that after 30+ years announced that they had been mistaken. Some month's after a talk at the DC/RC, about how some had decided they were because of how seemly extra devoted to study of the bible, and prayer, also being deeply involved in everything service related!!!