Things Noah & Finn have clearly been told they’re allowed to say to fans if Byler comes up:
At this time you may not say that you personally ship Byler
“It depends on what the Duffers write”/it depends on how the show goes/we’ll see what happens
“Ship what you want” <- a non-answer that intentionally walks the fine line between discouraging and encouraging
At this time you may talk about your personal feelings about the Byler ship/Go ahead and say “yes, I ship Byler” if you are directly asked
If pressed for more details you may say “there will be more of that in season 4 - you’ll see” <- intentionally encouraging without revealing anything specific
Pretend you don’t know what canon means lolol
This is me guessing what they’ve been told they can and can’t say based on how they’ve answered fan questions so far.
It’s important to note that I am taking the fact that they’re (almost certainly) being told how to navigate Byler-related questions as proof positive of canon Byler. (As others have mentioned, canon means different things to different people. I’m using “canon” to mean that their mutual romantic feelings will be both confirmed and central to the plot.)