Yes, you are able to change the time or date of your collection at any time after placing your order as long as your balloons have not already been inflated, for orders which do not include any inflated balloons you can change the time or date of the collection at any time.
You can contact us via email here: https://particaparty.co.uk/pages/contact-us
Most of our balloons are suitable for helium, you are able to select whether you wold like them inflated when they arrive when you add them to your basket or in your basket.