A patch for FAST RMX that enables online support between friends and also gives players an extra mode: Time Attack, will be released in the not-so-distant future according to a tweet by Shin’en Games. It would appear that the update is complete and ready to go live, we’re just now holding out for Nintendo to give it a release date.
We’ll no doubt let you know when that may be but I think we can expect it to be very soon.
As soon we get the release date by Nintendo we will post it here. It will be soon.
— Shin'en Multimedia (@ShinenGames) March 21, 2017

Beautiful game!
I’m probably going to get this soon, how would you say it compares to the wii u fast neo?
A lot better due to the fact that it’s portable!!
It’s great! You get 6 more tracks, 5 new vehicles and all previous vehicles return (some with new paint jobs) Hero Mode is available right at the start, online is smoother, and what Impact said: it’s portable!
Sweet! Can’t wait for it!
Excellent news! Nothing like freshly upgraded weaponry!