Which is different that the past when they stated it would be HDR10Unfortunately I downgraded my package from Xtra last week. It was needed for NHL 4k.
AT&T to Launch First 4K High Dynamic Range Live Broadcast
What the article doesn't mention is that the HDR is HLG, not HDR10 or Dolby Vision. So the true HDR experience will only be available to those with 4K displays that support HLG. LG and Sony do; not sure what others.