Your Flash now has 3 charges with a 2-second cooldown between casts (120 seconds recharge time for all 3 charges). If Flash is not equipped, you will be prompted to replace one of your summoner spells with Flash.
This augment page for Flashy reflects public Arena Mayhem data for patch 26.19.
No grade for this augment right now: it is not live, or the source has no reliable row for it.