I am resending this as a new topic as there was no response to it when it was added to another thread.
------------------------------------------
Plan year was changed from 05/01 - 04/30 to the calendar year with a short PY from 05/01 - 12/31 to align with plan sponsor's fiscal year change (no other devious reason).

The plan says (which is pretty much general language) that hours requirements will be proportinately reduced. So 1000 hours requirement for year of participation would reduce to 666.67 hours.

For anyone with more than 667 hours, is the S415 accrued $Max based on n+1 years of participation or n+0.667, where n is the accrued participation years at the start of the short year. It makes a big difference when n is on the low side, like 1!

Year of participation for S415 is the same as for the plan benefits.

You need to look at the definition of limitation year. Was it shortened? If so, plus .667. If not, then, plus 1.000, per limitation year.

On a second thought, giving a full year credit because of reduced hours requirement for a short plan year doesn't sound right.

What if the short PY is 1 month long? Would the participant receive a full year benefit accrual credit?

Plan design issue. Can go either way.