The new auto enroll regs allow for a 2 year cliff vesting schedule with an auto enrollment feature for a safe harbor plan. The advantages of the safe harbor plan is that ADP/ACP tests are satisfied. As long as you don't make any other contributions aside from safe harbor, top heavy is also satisfied for a safe harbor match. If you make a non-elective safe harbor contribution of 3%, you have made the top heavy required contribution even if your plan is top heavy.

I am sure that these forfeitures can be used for plan expenses, etc., but I am really interested to know if they can be used to reallocate to participants. More specifically, can you use a age weighted/integrated/new comparability type of an allocation method to make a discrationary profit sharing contribution in addition to the required safe harbor contribution? These new laws would seem to create one of the first times that there could be a substantial amount of forfeitures in a safe harbor plan.

I would think that a plan with a few highly compensated employees and a large number of short tenure lower compensated employees could really benefit if they could reallocate their forfeitures using one of the above methods. Furthermore, the HCE employees would not have to worry about corrective distributions and the could always defer the maximum.

You are correct that under the auto enroll safe harbor provisions, the plan automatically passes ADP/ACP. They are also not subject to top heavy rules unless you provide another employer contribution (including forfeiture allocations). You could do an additional 3% NEC, but you have to make sure that all eligible participants get it (not just those that deferred) and remember that top heavy minimum contributions need to be based on full year compensation, not eligible compensation. So depending on the size of the plan, you could be adding a large number of non-deferring participants, which could greatly increase cost and the effectiveness of allocating those forfeitures.