Accounting flexfield change

Hi All,

I need your help! it's Urgent.

Ive just finished to setup the General ledger, AP and AR. The applications aren't used (0 invoices,0 entries...)

my question is: Can i  update the Ledger and assign  a new COA (chart of account) .

the old and new COA have exactly the same structure, the same segments ,the same value sets and same values.

The COAs have only different  CVR and Security rules.

Can I do it  with risk = 0 ?

Thank you very much for your help

Mohamed