So this is my first job, I'm straight out of high-school and the job is a fiancial analyst thingy, I signed a contract with the start date as 4th september, today I got an email from HR saying the manager had confirmed the start date to be the 3rd of august, I am on holiday with my extended family till the 14th, what should I do? My dad is telling me just to say It wouldn't be possible for me to start then.