IMSA released Thursday the Sporting Regulations for the 2016 WeatherTech SportsCar Championship, featuring a number of minor changes for the upcoming season, which takes effect with January’s Rolex 24 at Daytona.

Here’s a brief overview of some of the noteworthy changes outlined in the 128-page document:

***A fourth driver will no longer be permitted for races between four and under 12 hours in length, although four drivers will still be allowed to compete in the Twelve Hours of Sebring. Up to five drivers will continue to be permitted in the Rolex 24.

***Drive time rules have been adjusted in the event of a red flag, with the minimum time to be reduced by a percentage of the time lost while the drive time was stopped. Minimum driver achievements may be adjusted by Race Control.

***IMSA has added “Driver Pairings” to the regulations for PC and GTD entrants, in an effort to maintain season-long points among teams. If a car does not complete the final 10 minutes of the race or does not complete more than 90 percent of the race, a driver pairing will be considered for the purposes of awarding championship points.

***Silver/Bronze-rated drivers must individually complete the minimum drive time for that driver or their paired (professional) driver to be eligible for finishing points, with the other paired driver needing to only drive the car in the race to be eligible for finishing points.

***Any third (unpaired) driver must individually achieve the minimum drive time in order to be eligible for finishing points. If the paired Silver/Bronze driver does not achieve the minimum drive time, the car will be placed at the rear of the finishing order in the class.

***Only one driver will be allowed to drive a car in qualifying.

***As previously revealed by Sportscar365, E20C fuel has been officially approved, joining E10, E85 and IMSA diesel as options.

***Testing has been restricted to a total of eight days for Prototype, nine days for GTLM and four days for Prototype Challenge and GT Daytona cars. Testing more than two consecutive days at the same track is prohibited, with testing within 14 days prior to the final day of on-track activity at a track hosting a WeatherTech Championship race event also not allowed.

***The new testing limitations do not count official sanctioned IMSA tests, such as the Roar Before the Rolex 24, with evaluation of 2017-spec Prototypes over the course of next year also being exempt from the 2016 testing restrictions.

***Details on the defined controlled engine parameters and boost control parameters, relating largely to the influx of turbocharged engines in the series, have also been confirmed, including applicable penalties.

***IMSA Continental Tire SportsCar Challenge technical director Jeff Mishtawy and Rob Elson have been added as supervisory officials, meaning they’ll be eligible to be among IMSA’s panel for official decisions.