Do I go by my new due date?

Alexis • Expecting our sweet baby boy in April.💙 I thank God for giving me such a wonderful opportunity!
My first due date was April 9th, which today makes me 9 weeks 6 days... But today the OB changed my due date to April 4th which today would make me 10 weeks 3 days... Do I start going by my new due date and start counting the weeks from 10 weeks 3 days?