Two Open Enrollments in same year?

Good Morning all!

We are looking to transition from fiscal year benefit plans with a 10/1 effective date to calendar year plans (01/01 effective).  We are having two open enrollments due to pricing changes as well as deduction frequency changes.  Our first enrollment will be passive and the second will be active (mandatory).

Has anyone in the community transitioned from a fiscal year plans to calendar year plans (or vice versa)?  If so, did you use two open enrollment events or did you use another method to update the event? Do you have any best practices or recommendations to share?  Thanks very much for your time and feeback!