Can I change the start date of the Contest that I have created?

You can always change the start date of the unpublished contest or a sweepstakes before it has been published. However, once you have paid for and published a contest or sweepstakes, you can no longer edit the start dates. This is a built-in feature to prevent users from changing start dates of active promotions, which is against laws and regulations for promotions in many jurisdictions.