ORCHARD PARK, N.Y. -- In early April, the Buffalo Bills made headlines around the sports world. The team traded four-time Pro Bowl wide receiver Stefon Diggs -- Buffalo's leading receiver for four seasons who set several franchise records -- to the Houston Texans.

The move marked the latest change of the Bills' offseason. In the end, the team moved on from six of eight team captains from the year before -- although safety Micah Hyde did sign to the practice squad in December. The transactions appeared to set up a bridge year for a team coming off four consecutive AFC East titles. 

More responsibility was set to be placed on younger players' shoulders, quarterback Josh Allen would be tested, going into the year with only one wide receiver who had caught a pass from him in a game (Khalil Shakir), and two young coordinators were taking over playcalling (Joe Brady and Bobby Babich).

Yet, general manager Brandon Beane wanted to make something clear.

"Anytime you make a move like this ... [it's] very difficult, you're doing it, you're trying to win," Beane said in April. "And sometimes people may not see that. This is by no means the Bills giving up or trying to take a step back or anything like that. Everything we do, we're trying to win. And we're going to continue to do that. It's April [3] and we'll continue to work on this roster and make sure we're ready to play come September."

Just prior to kickoff of the 2024 season, the Bills had a 43.6% chance to win the AFC East, the lowest of any projected division winner, per ESPN Analytics, with the projected second-hardest schedule in the NFL. Buffalo would defy that forecast to become the first team to clinch its division and defeated two eventual 14-win teams (Kansas City Chiefs and Detroit Lions).

As the regular season is set to end with a game at the New England Patriots on Sunday (1 p.m. ET, CBS), this version of the Bills (13-3), led by coach Sean McDermott, has become a record-breaking team that has surpassed outside expectations. Allen playing at his best -- a potential MVP level -- has led the way. The next step is advancing beyond the divisional round of the playoffs -- after losing in the divisional round the past three seasons with only one AFC Championship Game appearance in Allen's career.

"The question was asked [earlier in the news conference about the team's doubters]. When Josh comes in and he's set on what he wants to get done he's hard to stop," McDermott said after a Week 17 win over the New York Jets. "And so, he came in the spring and then again in training camp when he reported back, and you could tell he had a goal in mind. He's led this team right from the jump."

Allen's mindset has extended to the whole team, or as he described, "I am in a spot in my career, in my life where it's the best I've ever felt."

Questions surrounded the offense this offseason on the topic of how Allen would perform given the limitations on improving a team that took on $31.096 million in dead cap money after trading Diggs, highest for a wide receiver in a single season. The Bills offensive philosophy from the jump emphasized "everybody eats" -- the idea that every player has to be ready to receive the ball at all times. 

The offense has in turn excelled thanks to a variety of players. The Bills tied the NFL record in Week 17 with their 13th pass catcher making a touchdown pass in a season.  

The offensive line has performed at a high level and assisted Allen with the lowest sack percentage of his career (2.6%), along with career-best performances from the likes of running back James Cook -- second-most rushing touchdowns in a season in Bills history (15) -- and wide receiver Mack Hollins. Shakir has continued to be dependable (second highest reception percentage among NFL receivers with 90 or more targets, 76.8%).

Other players, such as rookie Keon Coleman, veteran Amari Cooper -- who was acquired via trade in October -- and tight end Dalton Kincaid have flashed while dealing with injuries this season and figure to be instrumental moving forward. 

"It starts with that unselfish approach. Don't get me wrong, we've got guys ... they get irritated when they're not the ones scoring the touchdowns or getting the ball or getting the sacks," McDermott said. "... That's kind of natural for competitors, right? But they, at the end of the day, know that what's most important is that the team does well. So, it takes a little bit of swallowing their pride from time to time and their ego."

While the defense has performed inconsistently, struggling at times this year -- especially on third down (fourth worst at 44.4%) -- takeaways have been vital to this unit. The Bills lead the league in turnover margin at +23, tied for the league high in fumble recoveries (13), while the offense's eight turnovers could tie the 2019 New Orleans Saints for the fewest in a season since 1933.

"We're peaking at the right time," Babich said, "and certainly, we know what time that is."

The unit still has work to do with the biggest challenges awaiting in the postseason.

"[We're] still in transition," cornerback Rasul Douglas said. "When they said transition, they meant transition from going to the AFC Championship to divisional round to a Super Bowl. That's what they meant when they said transition. Y'all just took it the wrong way."