If you’ve gone through the endgame currency transition before an expansion in Final Fantasy XIV before, everything that’s about to happen when the game switches gears into Endwalker will be rather familiar. It is possible you haven’t, though, and you’re not used to how the game’s endgame currencies will translate to a new expansion. Fear not, as the developers have put together a useful explanation of how the currencies of tomestones and both crafting and gathering scrips will change ahead of the expansion launch.
Allagan Tomestones of Poetics will remain the endgame currency for non-current content, with Allegory and Revelations tomestones available to exchange for Poetics and the already deprecated tomestones of Phantasmagoria being removed from the game (so exchange those already). Similarly, yellow crafting scrips will be waving goodbye, with the option to exchange them for white scrips while red scrips will be removed altogether. You’ve got just about a month to exchange the outdated currencies you might still have kicking around, so do that sooner rather than later.Source: Official Site