Only one hotfix in this batch, as the costs for the PvP Essences have been lowered significantly. This comes after Blizzard fixed a bug that was allowing unintended sources of honor to count towards the relevant achievements, and this change should offset that.
October 2 (source)
Heart of Azeroth
Blood of the Enemy, Artifice of Time, and Sphere of Suppression Rank 2 now requires 10,000 Honor (was 15,000 Honor) and Rank 3 now requires 30,000 Honor (was 50,000 Honor).
Developers’ note: We fixed a bug that incorrectly allowed Honor rewarded from quests and mercenary mode bonuses to contribute toward the “Battlefield Brawler” and “Battlefield Tactician” achievements required to unlock these Essences. To account for the quests and mercenary mode rewards no longer contributing credit toward these achievements, we have reduced the Honor amount necessary to earn these Essences. Rank 4 for these Essences will remain unchanged. Players who are now at or above the new Honor value will need to earn some Honor for the achievement to update.