IMSA class structure changes for 2018 and beyond

More news from IMSA, and that is, from 2018 onward, the Prototype Challenge class, will be dropped.

WeatherTech Championship Moves to Three-Class Format for 2018
http://sportscar365.com/imsa/iwsc/three-classes-for-weathertech-championship-in-2018-no-pc/

...and

Prototype Lights will be replaced officially, by LMP3 cars that are currently being run in the European Le Mans Series and will continue to be run there.

LMP3 is IMSA Prototype Lites Replacement for 2017
http://sportscar365.com/imsa/lmp3-in-imsa-prototype-lites-replacement-for-2017/

Positive Reactions to LMP3 in New-Look IMSA Prototype Series
http://sportscar365.com/imsa/positive-reactions-to-lmp3-in-new-look-imsa-prototype-series/