Those heading to Denver International Airport for redeye flights this month may experience a few delays as the airport prepares for new trains. 

The airport will be shutting down the trains to concourses B and C from 9:15 p.m. to 3 a.m. on Feb. 13, 14, 20, 21, 27 and 28. The trains will be shut down for the evaluation and testing of the “AGTS (Automated Guideway Transit System) power distribution system and the critical infrastructure systems,” the airport said in a Thursday news release.

Passengers needing to get to the B and C concourses during the shutdown hours are asked to head through Bridge Security and then look for personnel or signage that will guide them to a bus service. The bus will take passengers to the further concourses.

People heading to DIA during the shutdowns are asked to arrive 30 minutes earlier than initially planned, the release said.

The testing is in preparation for the 26 new trains being added to DIA tracks this year, according to the release. 

The new trains come as a welcome addition to the airport, which has experienced recent issues transporting travelers between concourses.

For example, on Jan. 23, a track switch plate issue caused trains to run at limited capacity, leading to a bevy of delayed passengers and people stuck at the terminal. It was fixed by the morning of Jan. 24.

For another example, a train got stuck on the tracks on July 5, 2022, stopping the trains entirely for around 30 minutes. 

“This effort will help ensure the resiliency of our automated people mover, the train, by evaluating the condition of aging electrical infrastructure while also providing critical information required for current operations and future expansion as we work toward 100 million annual passengers,” CEO Phil Washington said in the release.

The first of DIA’s new trains arrived in December of 2023. The new Alstom train cars are lightweight and energy efficient, according to a previous press release. They will lower power consumption for the train system by 30%.

Twenty-six of them are supposed to be on the tracks by the summer. First comes testing, though.