Again, if homologation rules are followed, yes. Minimum weight at 1245kg. So while they could go under 2700#, there really is no compelling reason to compromise the design to do so. If it naturally happens, good for them!
But this could be another thing FIA waives. The new GT COULD be an eye opener for them. With new/modern design practices there is no reason that they shouldn't consider adjustments to alot of their base car specs.
Go read the doc, it's not real long and you only have to read the right column since the left is all french and you can skip over detailed parts like wing design - which says when a thing "is a wing".