My answer:
For PC and Mac: Buy after February 17 but before March 17.
For Xbox One and Playstation 4: Buy after May 9 but before June 9.
Reasoning:
1) The Elder Scrolls Online now cost $59.99 USD while The Elder Scrolls Online Imperial Edition now cost $79.99 USD on Steam Engine. Amazon is showing pre-order of Tamriel Unlimited to be costing $59.99. Now you know the cost, read on to my 2nd point!
2) If you buy ESO after those dates, you will still have some subscription days left when Tamriel Unlimited is launched. You will then get 500+100+1500 = 2100 CROWNS! But why?
Please refer to this FAQ from the ESO's website (https://help.elderscrollsonline.com/) under How do I get crowns?
"There are several ways to get crowns:
1) As a new player: New players will be given a one-time gift of 500 crowns for buying the game and creating a game account.
2) As a current subscriber: If you are an active subscriber when The Elder Scrolls Online: Tamriel Unlimited launches, you will receive 500 crowns for having a game account, plus 100 crowns for each 30-day period you have been an active subscriber. In addition, you'll be automatically enrolled in ESO Plus for the remainder of your subscription period. You'll receive the full benefits of membership, and 1500 crowns for each 30-day period remaining on your subscription. For example, if you have 30 days or less remaining, you will receive 1500 crowns. If you have between 30 and 60 days remaining, you will receive 3000 crowns. 60 to 90 days, 4500 crowns.
3) As a returning player: If you've previously played The Elder Scrolls Online, but are no longer a subscriber, you'll receive 500 crowns when you log in for having a game account, plus 100 crowns for each 30-day period you were a subscriber.
4) Purchase Crown Packs: PC/Mac players will be able to purchase crown packs from The Elder Scrolls Online store. Console players will be able to purchase crowns via the Xbox Live or PSN stores." Please comment below if it's helpful!
