Single Member LLC

[SMB]

Individual sold the assets of his single member LLC (assume it was an "asset" sale, since there was no "stock", per se, to sell). Same individual subsequently established a new single member LLC and wants to set up a PS Plan for the new LLC. Some of the employees of the "old" LLC are now employees of the "new" LLC.

Must/may the PS Plan of the "new" single member LLC take into consideration service performed for the "old" LLC for initial eligibility and/or vesting under the new PS Plan?

Thanks!