This is part of the Psionic Mastery description from the Unearthed Arcana Mystic rules:
Beginning at 11th level, your mastery of psionic energy allows you to push your mind beyond its normal limits. As an action, you gain 9 special psi points that you can spend only on disciplines that require an action or a bonus action to use. You can use all 9 points on one discipline, or you can spread them across multiple disciplines. You can’t also spend your normal psi points on these disciplines; you can spend only the special points gained from this feature.
I think that it is not well explained and I didn't find clarifications around.
So, when I use my action to activate this new type of psi points I also choose the disciplines I want and they takes effect all together? Or I need one turn to activate this ability then another turn to use one disciplines, etc. until I finish this pool? Finally, Disciplines are block of several options, then does it means when I choose to use this bonus points the entire block is inaccessible with normal psi points?