HCM: Secondment best practice where assignment changes mid secondment

Summary

Any advice and guidance welcome

Content

Do you have a best practise for secondments that you might be able to share with me please?

Essentially, we have allowances that are paid to employees whilst the employee is on secondment. The secondment action is selected when a new assignment is recorded. The secondment element is then applied automatically where action reason equals secondment.

However if an employee is on a two year secondment and they change hours mid-way through the assignment then we lose the action reason and the automated element stops and the employee is underpaid.

Any advice and guidance is welcome,