Limitation Year different than Plan Year

[Guest Golden401k]

Example: Calendar Year Plan Year (12/31/2010) with 3/31 limitation year.

How does this impact my allocation and testing definitions? I 'm beyond the follow-up question of why isn't the plan year the same as the limitation year. That would be too easy.

Additional Facts: 1/1 and 7/1 entry dates and plan measures compensation from entry date. Plan Document: Corbel VS.

Compensation Definition in Doc: W-2 wages (plus elective deferrals) earned during the Employer's Fiscal Year that ends in the Plan Year.

I'm measuring allocation compensation from 4/1/09 - 03/31/10 for allocation purposes. I'm assuming my compensation limit and 415 limit is based on 2009 numbers because the limitation year begins 4/1/09.

What happens to the 7/1/10 entrant who apparently doesn't have compensation for allocation purposes in the 4/1/09 - 03/31/10 window?

Plan has last day and 1,000 hours rule for profit sharing allocation. I believe this is ok.

I would use 4/1/09 - 3/31/10 comp definition for 401(a)4 nondiscrimination testing.

ADP testing compensation. This is where I'm confused. I have a full plan year (1/1/10 - 12/31/10) worth of deferrals and understand the 402g limit is not impacted since it's a calendar year limit. I would think I would use calendar year compensation since it corresponds to the deferral period, but I'm unsure since it doesn't match the plan compensation definition period.

Does the limitation year have to correspond to the compensation definition period for allocation purposes? Example: Is it possible to have a 12/31/10 (calendar/plan year) limitation year, but the plan defines compensation from 4/1/09 - 03/31/10.

Is this getting ridiculous?