This is what Rovio said on their support page:
The Event Coins are linked to each event and they will expire when the event ends. The coins will convert into Feathers, but at a lower rate than buying them in the shop.
Pro-tip: Make sure to spend the coins before the event is over to make the best of them!
See? At A LOWER RATE THAN BUYING THEM IN THE SHOP! I only have about 147 ( had almost 2000) so I believe I will get 147 feathers as well. I am freaked out (kind of) because none of my birds are close to leveling up. I recently upgraded my slingshot and am waiting for the Feather Frenzy event because that is when I am going to claim the 30 000 feathers it will give me, and they will go straight to Chuck because his level is Pristine Diamond and he needs 30 000 feathers to level up again. So there is no way 147 feathers will level up one of my birds, but they will go into Leonard, I think, so I won’t need too many feathers to level him up. But I don’t think you need to know what I just said. Just keep in mind that this will always happen.
Another thing that ticks me off is that items can be sold out, unlike the Mighty Eagle’s shop. The best example I can give you is the Free Birds Tokens. I had 1847 Event Coins but I knew there was no way I could save up 2000 before the event ended so I spent them on other stuff. I actually wanted to spend all my coins on the Free Birds Tokens and decided to buy 8 of them. I only bought about 5 of them when it read ‘sold out’ and today ‘sold out’. I understand with the hats in Mighty Eagle’s Shop that you can only buy them once and it will read ‘purchased’ but how come the items in the Event Shop can be sold out as well? I don’t get it at all. Of course, it isn’t great that the Event Coins expire, but you know what Rovio is like. They want money, just like everyone else. And by the way, when it read ‘sold out’ just spend them on other items so you don’t get those measly feathers that you never wanted.
Airplane Lover