Termination approval based on the length of service

Summary

Can we set a termination approval rule for an employee based on the length of service.

Content

Hello Team,

We have a requirement stated below:

1.The initiator is Line Manager

2. The employee (going to be terminated) is having specify User Person type and his/her length of service is more than 20 months

Then it should go for an approval (Application role).

Would really appreciate if someone can help me or guide me with the solution if the requirement can be achieved. Also, I couldn't find any specific attribute like Length of service.

Waiting for some valuable suggestions.

Regards

Saikat