Fans learned last night that NBC changed its fall 2017 schedule. After initially sharing that "This Is Us" would move to Thursday nights in the fall, the network has now decided to keep its Tuesday 9 p.m. slot. However, there is bad news for "Chicago Fire" fans, as season 6 will now air on Thursdays instead of its usual Tuesday night 10 p.m. slot. Fans around the world want to know why the network has decided to do this.

Problems due to Thursday Night Football

One of the main suggestions offered is that Thursday Night Football would cause a problem.

"This Is Us" would have just seven weeks until football would interrupt the planned scheduling, forcing it to go on break sooner than many fans of the show would like. There are some questions over whether NBC feared for the fate of the popular dual timeline show, which is only in its sophomore year.

While "Chicago Fire" will now only have seven uninterrupted weeks, it does have loyal followers. This is a show that is on its sixth season. While it is rated lower than "This Is Us," it has had longer to cement its place on the network.

Going up against Shondaland Thursdays

ABC currently holds Thursday night viewings, with CBS fairing well too. When NBC decided on its fall 2017 schedule, it didn't seem to take Shondaland Thursdays into account.

"This Is Us" would go up against the confirmed final season of "Scandal." Maybe the network feared that it wouldn't hold up against the political drama.

"Chicago Fire" has a chance to hold up against its 10 p.m. contender "How to Get Away With Murder." It no longer has to face off against "NCIS: New Orleans," which is one of CBS' best shows.

The only wild card in the Thursday 10 p.m. slot is the new "S.W.A.T" from CBS with Shemar Moore.

NBC may believe new ABC series will air on Thursdays

There is also the possibility that NBC is trying to plan ahead for the upcoming "Grey's Anatomy" spinoff. Nicknamed "Seattle Fire," it's clear that this is an attempt by ABC to go up against the "One Chicago" series.

It is possible that NBC believes the fire series will air on Thursday nights and is trying to cement its own fire show there before ABC has a chance.

Working against NBC is that "How to Get Away With Murder" will likely have the same number of episodes as it did this season, taking it to a March 2018 finale. "Seattle Fire" isn't supposed to air until the midseason, so it could clash with the breaks for "Chicago Fire."

NBC has yet to explain why it made its fall 2017 schedule change. Fans aren't happy, but more so because they dare not plan ahead for the fall season now.