LOS rules should work from continuous start date (if present), not start date

We have many many employees with a Continuous start date (the date they joined the company) and a start date (the date they started their most recent role).

We also have LOS rules set up to add rewards based on number of years since starting the company.

These rules however are only triggered on the start date, which is clearly wrong. This needs to be changed to:

If continuous start date exists then use this, and if not, use start date.