Early access...whats the point?

[Alberel]

The main purpose of early access is to make it a 'must have' to get almost everyone pre-ordering. The pre-order numbers gives SE a rough guide for how many people might be coming back to the game for the expansion and they can prepare accordingly for those numbers on the 19th. It's a clever move as they won't get surprised by a surge of people buying that did not pre-order since the only way into EA is via pre-order.

There'll be a small additional spike on the 23rd but nothing compared to the 19th.

Iirc, new tomestone will be released 2 weeks after launch, together with Alexander.

It is only Esoterics that will be released later. Law will be released with the expansion.

[Nutz]

It is only Esoterics that will be released later. Law will be released with the expansion.

That's true, but esoterics are the capped tomestone and law are uncapped, so EA doesn't allow players to gain any extra tomes except that time allows (no cap reset). I know it's not mentioned in the bit you quoted, but Kit-Kat was responding to someone suggesting EA provides an extra tome reset week.