What time does the Will Call window open?

[pgsahm2]

We will be leaving on my son's birthday (12/17) from WDW and heading to board the Wonder. Magic Kingdom has early EMH that day. We'll need to go to the Will Call window to get his Birthday Fun Card but I don't know what time it opens. Does anyone know how early it will open on an early EMH morning?

Thanks!

 

[Robo]

We will be leaving on my son's birthday (12/17) from WDW and heading to board the Wonder. Magic Kingdom has early EMH that day. We'll need to go to the Will Call window to get his Birthday Fun Card but I don't know what time it opens. Does anyone know how early it will open on an early EMH morning?

Approx. 30 minutes before the park admits guests.