In January, Herndon pleaded guilty to driving while intoxicated after crashing into a 76-year-old-man's car in Rockaway Township, New Jersey, in June 2018. Herndon's blood-alcohol level of 0.14 was well over the legal limit.
Herndon is expected to be New York's starting tight end in 2019 after the Jets selected him in the fourth round of the 2018 NFL draft out of Miami.
Per NFL Network's Ian Rapoport, Herndon's suspension was four games rather than two because a woman at the scene of the June 2018 crash claimed bodily harm as a result of the incident.
The 23-year-old Herndon made a significant impact for the Jets as a rookie last season with 39 receptions for 502 yards and four touchdowns. He finished second on the team to wide receiver Robby Anderson in catches, receiving yardage and receiving touchdowns, and seemed to build a strong rapport with rookie quarterback Sam Darnold.
New York should have a much-improved offense in 2019 with the additions of running back Le'Veon Bell and wide receiver Jamison Crowder, as well as the return of wideout Quincy Enunwa from injury.
The Jets did little to address the tight end position, though, aside from selecting Trevon Wesco in the fourth round of the draft out of West Virginia, although Wesco may be utilized more as a fullback than a tight end.
Darnold may not look to his tight ends much during the first month of the season since his options are unproven beyond Herndon.
Daniel Brown has 35 career catches and didn't make a single reception with the Chicago Bears last season, while Eric Tomlinson has 16 career grabs and finished last season with eight receptions for 72 yards.
Herndon remains eligible to take part in training camp and the Jets' preseason slate. During the regular season, he will be eligible to return on Oct. 7 following New York's Oct. 6 game against the Philadelphia Eagles, and he can then be activated for the Jets' Oct. 13 clash with the Dallas Cowboys.