The date May 5th is when they are going to stop giving away eevees. This is why you have to wait. My problem is that I can't get it to save in the first place. I've seen several people have had the same problem and have read up on several suggestions to get it to save, but so far nothing has worked. Each time I confirm my choice of Leafeon twice. After this, there is a screen that pops up that asks if I want to Play Again. Most suggestions on the net said to not click Play Again. Some say to click another link or to just exit from the web browser. I can confirm that neither worked for me any of the times attempted.
After this fail I clicked Play Again. Completely played through again, and was not shown the Eevee prize screen so I thought this worked...NO. My first clue was that I had a new High Score of 86,000 but the character screen of mine was not updated with this score.
Next I played all the way through, picked Leafeon and then hit the Play Again button. I purposefully lost in the first round just to see if that would cause an interrupt allowing Leafeon to be saved...and No again.
Is anyone else having as much problems with this? And before you say it's saved, you should make sure.
Edit: I switched browsers and it worked! Leafeon is now successfully saved, and now I'm going to work on getting my Glaceon.
Edit 2: Glaceon is now confirmed saved after several attempts to save. Switching browsers was only a fluke. What seems to have worked was to clear my cache, history, and cookies. This was the only thing in common with the two successful saves.