Change in vesting schedule

[Doghouse]

ABC Corporation has 401(k) Plan A and has now started a new 401(k) Plan B. Both plans have a six year graded vesting schedule.

Plan A does not exclude YOS prior to the plan's effective date (1/1/06) but Plan B does (actually the effective date of the plan or a predecessor plan). The effective date of Plan B is 1/1/09. I don't think there is any question that Plan A is a predecessor of Plan B.

Currently Plan A is in the process of merging into Plan B.

If anyone can weigh in on the following issues, it would be much appreciated.

1. Does everyone agree that the change in vesting schedule rules apply here?
   
2. If 1 is yes, would you treat the vesting protection as applying only to amounts already accrued in Plan A, or to future accruals as well? I know the IRS takes the position that the protection applies to future as well as to past accruals, but I get the impression that this isn't necessarily the position embraced in the field. Nor does the IRS position specifically address plan mergers.
   
3. If 1 is yes, do you agree that the three YOS to determine who could make a vesting schedule election applies to all YOS, not just those subsequent to the effective date of either Plan A or Plan B?
   

Thank you for any and all replies!

P.S. I believe Plan B was created to get around the pro-rata safe harbor allocation rules for nonelective contributions in Plan A. It did not just "happen" to exist.

Dog