Can I trigger a flow around a specific date (i.e. July 4) instead of selecting a date property?
No. In order to trigger emails around a specific set date, like July 4, you would also need to choose your target audience for these emails. To achieve this, you must schedule a campaign to a target list/segment on the date of your choosing. To schedule a series of emails leading up to a single date, you can use scheduled campaigns to ensure that each email is prepared in advance to send at the right time.