I sold my scorp and buyer got a new EIN before the sale- do we do 2 different tax returns because of the 2 EIN's?

My son and his partner bought my scorp but applied (and received) a new EIN prior to the sale.  Does this now require us to do two different tax returns? I'm assuming I would do a return for the business using data from before the sale, my son would use data from after the sale, and I would notify the IRS that the business with my EIN ended once the sale was completed