update Additional Period of Service DFF when terminating an Employee using API

 I am trying to automate Terminations. I looked at both Term and final process API , but do not see an API to update Additional Period of Service DFF API.

We have "Employee Eligible for Rehire Flag"  in that DFF, we want to update that FLAG - when terminating an employee using this automation process.

or Any other alternate solution that I can do ?

Thanks.