Does anyone know what time zone the Guild Siege times are in?

I’ve been trying to figure this out since it got released, but I know it didn’t work properly the first week or two. But now I see that guilds were able to compete last week in the PvP Guild Siege islands like Naruni and Snowpang. I just don’t want to miss my chance at it this week for my guild.

So does anyone know what time zone it’s set in?