UNDERSTANDING THE THREE FORMATS IN STAR WARS DESTINY:
This is the easiest format to remember. Infinite Format allows for every single card to be used. It is the Star Wars Destiny equivalent of Magic the Gathering "Vintage". Not really much to say about it. If you own the card, you can use it!
You will probably not be seeing a lot of official events in Infinite Format, and it was probably made mostly to keep players with big collections of "older sets" happy, and ensure that they would still have a format to play all their cards in. I suspect it to be more of a niche format!
Standard Format, is the official premium tournament format, and changes as new sets are being released and includes according to the Fantasy Flight Games' statement:
Now, the most confusing thing about the format description is that it says in the official statement that "products that are part of an unreleased cycle" can also be used. If you are confused about this, then it's because you don't know how Fantasy Flight Games usually operate. A lot of good things can be said about FFG, in particular the quality of the games they release, but one thing that is particularly bad about them is there release schedule. That is "when new sets are being released".
A "normal company" would release Product 1, then Product 2, Product 3 and so forth. And normally products would be released according to an official release schedule, so costumers know when various products would be available! FFG operate in a different way. VERY VERY DIFFERENT WAY!
Fantasy Flight Games release products RANDOMLY!
This is of course not entirely true, it is merely the observations of a customer, but it essentially means that while a "cycle" of products have not been fully released, i.e. you are still waiting for the last expansion of the "Legacies Cycle" (The Across the Galaxy expansion which is marked in a dashed box in the graphics above), they might decide to release the 2 new Starter Sets for the "New Cycle", which then in turn means that they would become immediately available for the Standard Format because they would be a product forming a "part of an unreleased cycle". Confused? Perfect!
This essentially means that all products released thus far will be eligible in Standard Format, but when the NEW CYCLE officially begins (after the release of a full set to complete the Legacies Cycle AND the release of the first set in the "New Cycle"), then the Standard Format will look as follows:
This change in the Standard Format is likely to take place in the beginning of 2019! Which means that all your "Awakenings Cycle" cards will be valid for Standard Format play until 2019, and after that only valid in Infinite Format.
OR PUT VERY BLUNTLY:
If you buy cards from the Awakenings, Spirit of Rebellion and Empire at War Expansion Sets (all the ones in Black packaging), they will be worth nothing (apart for collectors) as of early 2019!
For an even more limited format, meaning more restrictive in the cards that can be used, Destiny uses the Trilogy Format. The Trilogy Format is the "easiest format" to enter for a new player because it exclusively uses the newest cards, which also means the card pool is much smaller (currently 406 cards as opposed to 900 cards currently in use in Standard Format).
The same "rule of thumb" as in the Standard Format applies to Trilogy Format: If FFG decides to release a product associated with a future set (unreleased set) before the end of a current cycle, i.e. the Legacies Cycle, it would automatically be included in the Trilogy Format. CONFUSED? PERFECT!
We will continuously update the various cycles here and make sure that the formats are up to date!
LAST UPDATE July 20, 2018:
Modified following the announcement of the Sixth Expansion: Across the Galaxy (scheduled for release in November 2018).