Remove accrual policies from employees profile

Dear Personio community,

Personio recently came with the feature of round up rules for accrual policies. Before that, we manually adjusted employees their vacation days. 

Let's take our example of Germany:

We first had a policy for 25 days for Germany, after we changed that to 26 days. Right now we still have 26 days, but we wanted to create a new accrual policy with other round up rules. 

I actually would like to remove old accrual policies from this overview, because it can be very confusing if there are so many versions. I called the newest ones (with new round up rules) all ‘…. - New’. But actually, we would like to be able to remove them. I also know that that isn't possible if they are assigned. 

How can we make sure to remove the accrual policies from this overview, without removing people their assigned vacation days the past years. I don't want to mess up people their personal balance.

Thanks!