How to override EE rate in OAB for just one employee

Requirement - A potential new hire will be offered Plan A but will require an override to the EE contribution ,an amount different than what's set up in the system(Variable rate).all other employees should continue to get the rates setup in the system except for this employee. is there a way this can be addressed. Can we use rate overrides in this case? If so I am looking for exact steps to implement the rate override.

Please let me know if you need any additional information.

We are 12.1.3  DB 11g

thank you

Shilpa