I want to add annual paid leaves on People and have it updated automatically.

The vested leave dates are calculated as follows;

1- Leave is not entitled until 1 year from the date of employment.

2- Leaves of employees between 1 year and 5 years are 14 days

Leaves of employees for 3 - 6 years and over are 21 days.

Each person has to calculate this calculation based on the date of employment.

Can you assist me on how to do this?