On their first day of having a standby line, we followed the wait times for Guardians of the Galaxy: Cosmic Rewind and Tiana’s Bayou Adventure.
Tiana’s Bayou Adventure

Tiana’s Bayou Adventure at Magic Kingdom did not initially open with the rest of the park as it experienced a delayed opening.
The opening of the ride was delayed due to “technical difficulties.” At 9 a.m. guests were able to enter the standby queue despite the ride not operating.

At 9:38 a.m. Tiana’s Bayou Adventure was opened for guests and the wait time was at 45 minutes.

Ten minutes later at 9:48 a.m., the attraction was still at a 45-minute wait.

Less than 20 minutes later at 10:02 a.m., the ride had dropped to just a 20-minute wait.
The low wait times in the morning were likely due to colder temperatures as it was only 61°F with the high for the day being 68°F.
At 11:20 a.m. the wait time increased to 40 minutes. Over the next hour, the wait time fluctuated dropping back down to 25 minutes before reaching back up to 40 minutes again at 12:23 p.m.
By 1:37 p.m. Tiana’s Bayou Adventure dropped down to a wait time of 35 minutes and almost an hour later at 2:23 it reached 55 minutes.
At 3:34 p.m. the ride only dropped five minutes in wait time to 50 minutes and reached 60-minutes at 4 p.m., the longest wait for the day up until that point.
At 5:00 PM the line wait time stretched to 65 minutes.
When we checked back at 6:40 PM, the attraction was down. By 7:40 it was back up with a 25 minute wait. At 9:00 PM it was down again, and with temperatures in the 50s, from what we could tell, it did not reopen.
Guardians of the Galaxy: Cosmic Rewind

Guardians of the Galaxy: CosmicRewind experienced much higher wait times on opening day than Tiana’s Bayou Adventure. By 8:53 a.m., prior to the park’s regular opening time of 9 a.m., the line was at a 35-minute wait.

Just 20 minutes after the park opening the wait had reached 50-minutes. Within four minutes, at 9:24 a.m., the wait time skyrocketed to 170 minutes.
A few minutes later at 9:32 a.m., the wait time dropped to 135 minutes.
The wait time for Guardians of the Galaxy: Cosmic Rewind continued to steadily lessen over the next two hours and reached a 60-minute wait at 11:45 a.m. The ride’s wait time hovered between 50 to 60 minutes up until 4 p.m.
At 5:00 PM we saw the wait start to increase again, likely due to locals getting off work and heading to the parks. The wait was now at 70 minutes.
A check at 6:40 PM revealed a 75 minute wait.
By 7:40 the wait had grown to 85 minutes.
We will continue to monitor wait times to see if any trends emerge. Keep checking in with WDWNT.com for more updates.
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