If I am interpreting that correctly, it will not work like Shillings because you will be able to purchase Aquilas directly, whereas Shillings were a one-time bonus included with DLC purchases
There was a poll here a few years ago prior to the release of Shillings that while the sample size wasn’t very large, I think shed some light on how the community felt about purchasable currency: here
Bearing in mind according to info at the end of this video specifically at 01:07:30, all maps and content updates will be free to all players which may be why they are going this route
I guess some further clarification would be handy because I’m seeing a lot of posts elsewhere with people thinking it’s just going to work like Shillings
edit: slight clarification to this after Hedge updated about it – Aquilas are premium currency that you can only buy, and Tertium Twins is in-game currency that you cannot buy and are more like Shillings