How to add opening balance for member

Based on the previous financials, one member has two type of accounts. one is accumulation account, the other is account based pension account (retirement phase), how to add opening balance to my BGL, I had a couple of attempts, I created a accumulation account and key in the sum of both accounts , then open a pension account and transferred the balance in retirement phase to pension account. from what I can see the member statement now balanced to the previous financials, but now the pension account shows the convert to ABP option. I am not sure whether the process is right or not?