It updated before that time, I checked. I was online at 8;15 am Pacific time and the Gem store had updated and removed the Home Garden Plot I wanted to buy.
Note the Time I posted my comment, That's 11;32 am EST. which is 8:32 PST.
It's not 9am Pacific time. It's earlier. I set an alarm for 8am PST and they were gone. There needs to be an Actual time it expires listed. Just posting "Soon" doesn't say anything.