Does anyone know if retroactive disability payments would be subject to benefit restrictions?

I have a plan where the AFTAP is 65%. The plan pays an immediate disability benefit commencing when social security deems a person disabled. Sometimes social security takes years to make this determination. For example, the participant might receive a letter in 2009 stating they were disabled in 2007. In this situation the plan would retro pay disability benefits back to 2007. (disability is pure subsidy - not a retirement benefit)

I know the regs say "any payment", but I was wondering if for some reason ancillary disability payments might be exempt.

I went through this issue with a benefits attorney regarding accumulated monthly payments pertaining to a retroactive annuity start date. The conclusion was that these would be subject to the 436 restrictions.

OK, but since my AFTAP is greater than 60%, as long as the amount of the retro payments was less than 50% of the present value of the benefits, I can still pay it, right?

Yup, assuming the PBGC guarantee crud is not applicable.