Well, that tells us nothing. I can only assume that it's a "definitive edition," like they did for the Age of Empires games, but with a different name for some reason.
The premium pack seems like a bit of a cash grab.
I get the RTS genre is in a bad place right now but pay extra for 7 days early access, an exclusive god and the legacy pack (basically the original game icons). I'll get it because I'm a huge fan of the franchise but yeah.
I guess you get expansion 1 and 2 whatever that is. Probably just a new civilization like reworked China and then pick another for 1 or 2. Maybe the value is there.