Activating Segment level Characters subsequently

Hi Experts,

We want to activate two additional Characteristics subsequently (meaning in a live environment)at Segment level in Account based CO-PA. If any of you done this earlier, could you please let me know what are the things I should be aware of? Any special scenarios you tested? Did you encounter any issues, because of this change and if so, how did you fix it. Any cancellation of old documents created any problem?

Thanks for your time.

Regards,

SAP_CO1