Having the same issues as everyone else here whom ordered from Amazon UK. Originally I had no dispatch date, upon upgrading my shipping option to "Expedited" it gave me the date of the 26th May.
I knew chatting with them would be useless, but I tried. It was terrible. You can see the chat for yourself:
Me: I preordered the collector's edition on the 5th June last year, and it always said it was due to arrive today (19th) and then I received an email saying that you were trying to obtain the following items. Can you explain the situation to me?
I expected to get it today so I am very disappointed.
I upgraded my shipping options to "expedited" and now it HAS given me a dispatch date but not til next week! What's going on?
Amazon: Hello, my name is Suraj. I’m sorry to hear about this. I’ll be glad to help you.
Me: Can you confirm I will DEFINITELY be receiving the item? I have been waiting for it since last year.
Amazon: Is this the item "The Witcher 3: Wild Hunt Collector's Edition (PC DVD)"
Me: Yes
Amazon: Could you wait for a minute while I research this for you?
Me: Yes
Amazon: Thank you for your patience, Maria.
I am sorry for the inconvenience, Maria.
As I have checked your order will be dispatch on 23 May 2015
Me: It didnt have a dispatch date before however, it only has one now because i upgraded my shipping option to expedited.
Amazon: I am sorry but there are some problem going on with the release date and it has extended
Me: Can you not clarify what the problem is?
Amazon: There is a problem with the release date and the customer who have ordered first will be getting the item first.
Me: That's not true at all. I am on the games forums and people whom have ordered way after me have already received their game from amazon.
Amazon: I am sorry but as I have checked now the item is not in stock also.
Me: Has it not been out of stock for a long time now?
Amazon: I am extremely sorry but as the item is out of stock now you will get your item on Tuesday, 26 May 2015
I would request you to wait till Tuesday, 26 May 2015
Me: Okay thank you.
Amazon: Thank you for your support and trust with us.
Have a nice day.