Hi,
As you rightly said in your message,its going to be a entire rework, like you will have to edit, remap and run again.
Normally in BICS scenario, BO maps to Guid of each BW object and when the BW technical name is changed, these id's would differ and cause errors like unresolved objects...
I don't there is an automated method as solution for this.But am not sure if such a solution really exist or not!
BR
Prabhith