Looking at the regulations (google translated from French to English) it looks as if other "special prototypes" may be entered into the "P4" class, or new classes created altogether
https://series.ultimatecup.racing/ph...techniq....pdf
Depending on the available places:
P4 - Ultimate Cup series could accept this new generation of prototype:
o Ligier JSP4
o Pescarolo 04 open or closed version
o Etc ...
This category should have lower performance than the LMP3.
Classes could be created depending on the participants.