You’ll be purchasing actual WDW tickets from Undercover Tourist which will have valid timeframes:
Ticket Duration Valid Use Period
1-Day Ticket Only the start date selected
2-Day Ticket Any 2 days within 4 days beginning on the start date
3-Day Ticket Any 3 days within 5 days beginning on the start date
4-Day Ticket Any 4 days within 7 days beginning on thestart date
5-Day Ticket Any 5 days within 8 days beginning on the start date
6-Day Ticket Any 6 days within 9 days beginning on the start date
7-Day Ticket Any 7 days within 10 days beginning on the start date
8-Day Ticket Any 8 days within 12 days beginning on the start date
9-Day Ticket Any 9 days within 13 days beginning on the start date
10-Day Ticket Any 10 days within 14 days beginning on the start date