Expansion rollout strategy

[Jojoya]

The other stuff though I really don't get. I PAID for ShadowBringers - included in what I paid for IN FULL is the Heavensward and Stormblood expansions, which are products that are out and available now, not gated behind a release date.

The product is clearly marked as pre-order, which means you are reserving a copy in advance of release. You haven't obtained that copy yet and until you receive it, you would not have access to the things it includes unless it specifically states those items will be available in advance (such as the Aetheryte Earrings being available on March 1).

If SE has already charged your credit card or other payment method, you might have a case for expecting them to deliver the portions of the product already available since they have already received the funds but that would depends on the consumer laws where you live. Contact your local Consumer Affairs/Consumer Protection agency.