I found this story very surprising in a number of ways, so I gave some of the details a quick search.

According to the docs linked, there are two forms at play, SSA-454 and SSA-455. The author likely had to have an SSA-455 filled, as his condition is of a "Medical Improvement Not Expected" type (this differentiation does exist). Seems that this needs to be done every 5-7 years.

Both can be filled online apparently though, self-service style (not sure how accessible that is for him though):

https://www.ssa.gov/disability/review

Faxing and physical mail to a specific office seem to be additional options. Doesn't even sound like the fax and mail rule is office specific, seems to be a Social Security Administration originating internal policy.

Am I missing something?