Two day ticket date changes

Walt Disney World
1

So, we are planning two days in WDW in February. We THINK we know which days we will be there, but we could change our minds.

The problem is, a 2 day ticket only gives a 4 day window, but we have potential 6 days we could use it in. If I buy the tickets at the price point that is highest in that span, can I just change the dates online, or will I have to call regardless?

2

I don’t think you have to call even if you have to pay the difference. I have been able to modify dates of tickets in the app.