403(b) restatements with pre-approved language

[Belgarath]

Just wondering - suppose several school districts, (so non-ERISA plans) who all sponsor 403(b) plans, merge their plans into one 403(b) plan, effective in, say, May of 2017, using an IRS pre-approved prototype - should be available by then...

Do all of the individual plans have to be restated retroactively to 2009? I presume not, but I've never thought about it! Could get messy screwing around with 4 different plans with different provisions going back years and years.

[Peter Gulia]

The idea of requiring a written plan as a condition to section 403(b) tax treatment is the Treasury department's interpretation.  So if practitioners are in doubt about the answer, one should put the question to the Internal Revenue Service, because only its interpretation has much weight in practical application of the Treasury department's interpretation.

But let's ask the BenefitsLink community to test a hypothesis:  In using a preapproved document for a 403(b) plan, would one "document" the history of the plan's provisions to the same degree one would do so in using the similar kind of preapproved document for a 401(a) plan?

Also, does a preapproved document itself (in its adoption agreement and other instructions) tell a user how much of the plan's history of provisions one must or should record in the current document?