The 11880 is a three year old model, and some rumours whisper, or wish, a 11900 with the same features as the 79-9900 models.
Yes the 11880 getting a little old, plus the oddity that prints on a lesser sized 44" or 24" Epson x900's have better color gamut due to the HDR inks extra colors, than the 11880 with its older x880 inkset... despite it being Epson's most expensive pigment machine. But, they sell many fewer of the 64" models, so an update is not a priority, methinks.
Also there is not a huge rebate promotion on the 11880 at the moment - the classic sign of a new model imminent - there is just a $1000 offer, though it is a good deal at these levels. The 3880 has a $300 rebate on its $1100 price - near 30% which is a big red flag of the 3900 coming.
I would be surprised if they do announce the 11900 in the next month, but happily so!