Any member of the public employees' retirement system plan 2 who is employed in an eligible position as an educational staff associate and who elected pursuant to RCW 41.32.032(2)(a) to remain a member of the public employees' retirement system under chapter 41.40 RCW may make an irrevocable option before January 1, 1998, to transfer to plan 3 pursuant to RCW 41.32.817, PROVIDED THAT:
(1) Only service credit for previous periods of employment in a position covered by RCW 41.32.010 is transferred to plan 3;
(2) Equivalent accumulated employee and employer contributions attributable to service covered by subsection (1) of this section are transferred to plan 3;
(3) Employer contributions transferred under this section shall be paid into the teachers' retirement system combined plan 2 and 3 fund.