Fast track taking longer than a week?

Had an appointment for a 1st child's passport at the Liverpool office kn the 24th of April, was assured that we would receive our passport by 3rd of May. We fly on Saturday. This is after cancelling a prior application which cancelleation was sent off 2 weeks previous to our appointment. All good, thinking its going to arrive today however I've just had a text saying we will receive passport in the next few working days - we only have 3 working days left!! So I'm panicking. Has anyone else had this text and how soon after receiving it did your passport arrive