SAP HR Seniority based plans for benefits

Hi All,

I have created a plan for Savings plan based on seniority parameter group.

I have 0- 7 years(5% Contribution) and 7+ years(6% Contribution) seniority parameter group for the Savings plan.

So once an employee is enrolled in for 5% contribution and once he completes 7 years of service,whether contribution % changes automatically to 6%.

or Whether we need to re-enroll them and should give 6% contribution manually???

Thanks & Regards