(1) The state treasurer shall promptly credit the Tier 2 account of a qualified participant or former qualified participant who makes an election under section 50 to terminate membership in Tier 1 with any amount transferred from Tier 1 pursuant to section 51.

  (2) Not later than 30 days after receipt of a recomputed amount under section 51(2), (4), or (6), the state treasurer shall charge the participant’s Tier 2 account for any amount of excess transfers under section 51(1), (3), or (5) and transfer that amount to the appropriate fund in Tier 1. The state treasurer may determine which investment choice or choices within a participant’s Tier 2 account will be used for this purpose.