"Character Mythic Keystone Profile Index" missing "best_runs" in "current_period"

Before pre-patch the “Character Mythic Keystone Profile Index”

/profile/wow/character/{realmSlug}/{characterName}/mythic-keystone-profile

returned “best_runs” for the “current_period”. The “best_runs” is currently completely missing. Right now it only contains “period” and “id”.

Is this an oversight / issue of pre-patch or was this information intentionally removed?