Disadvantages of Override Plan Enrollment

We are currently overriding employee’s amount to a different rate as they are subset of people from the plan who have been ratified. We initially thought its only 25 employees but now additionally another 80 employees have to overridden with new rate. We would like to know what are the disadvantages of overriding employee’s enrollment rates? Will it affect during life vent or during open enrollment?

Thanks

Guru