@Background Pony #CA13  
Did you seriously use the word “faggot” unironically? I mean, I don’t have any issue with using the term light-heartedly, but specifically referring to LGBT persons with it? Really?

@Background Pony #CA13  
you realise that adding quotes or stressing a word can change the meaning?  
those quotes read like they are trying to hide the gayness via that word.  
even that 3rd quote sounds like more proof,  
“man i wish our company had more balls and our age rating was one higher so i could announce my undying love friendship for you.

@Minus  
Keep telling yourself that deliberate and overt ship-teasing ‘breaks’ it in some way, hon.

so very little fanon was broken… Except for the hilariously intentionally shattered Lyra X Bon Bon fanon. Makes this even more fitting.

And… the most popular fanon is pretty much all confirmed!! Plus, there is a huge twist about Bon Bon…

Can’t possibly be worse for my headcanons than Griffonstone.

@Manual_Monaro  
I’m mostly hoping that Bon Bon gets to keep her name, even if they can’t use it in the toys anymore… maybe they’ll get away with not referring to her by name at all, such as they can’t call Derpy Derpy anymore but they just use her face in place of any name.
 
But, as you (and the artist) say, this’ll probably be a headcanon smasher, but it’ll be awesome to see any of them get to do anything.

‘Ruining’ headcanons is (most likely) inevitable in a long-running series with a massive fan base like this. As has been said above, it’s impossible to please everyone (and not just with this episode’s concept).
 
Personally, I won’t mind how this episode will turn out. Lyra is certainly one of my favourite ponies and I’m hankering for the eccentric, spastic, excitable Lyra. That said, if she’s somewhat (or completely) different, I’ll be fine with that. Hell, her appearance/design is a large part of what I love about the ‘character’. Seeing my favourite background pony brought to life and having a bigger role within the narrative is just enough for me (assuming she does play a big part… I hope so)!
 
All in all, I love any and (mostly) all interpretations of Lyra: the human-obsessed one, the hand-obsessed one, the marefriend of Bon Bon/Sweetie Drops, the Background Pony one (;~;), the almost semi-canon excitable one etc. Same goes for other ponies like Bon Bon, Vinyl, Octavia, Berry Punch etc. I certainly have my ‘idea’ for how each ‘should’ be (headcanon), but I won’t worry if it’s broken by the 100th episode.
 
Anyway… The warning in OP’s description is rather apt. I hope plenty of people will heed it!
 
And as for the episode (and season) itself? So excited!
 
_{Sorry for my wall of text. :3}

As if season 4 didn’t ruin millions of headcanons and fanfics already…

Don’t think of it as losing a headcanon, think of it as gaining a canon. Now you can write stories about us them without fear of being overturned by future episodes.

I’ll be happy if Lyra is made fun. Bonus points if she’s eccentric.

Or… And this is a big or.
 
They’ll try their best to not totally crush any huge headcanons and try and do some small little things that only we would get, like lyra and bon bon gazing at each other, and will instead focus on them doing something that wont totally crush any headcanons too badly.
 
Nah, That’d be giving them too much credit.

It’s a good thing I have no headcanon for background characters.  
That’d be stupid.

@Ilsor
 
They said some will be familiar, and some completely different.

?they did pretty well with Vinyl, Octavia and Derpy.
 
But hey, don’t let me ruin another oh-so-tired “this fandom is so” whinefest for you, artist.

@Background Pony #2643  
At this point you simply can’t please everyone in a fandom of this size, ever.
 
It’s really about how many of the snowflakes wish to be heard about their headcanons personally getting overruled.

@Ilsor
 
Sadly, no matter what, we’re going to get…
 

@PonyPon  
Badly, IMHO.

@Ilsor  
They said ‘they know what’s popular’.
 
Who knows how that will turn out.

Didn’t they say that they tried to incorporate some of the fandom’s vision for these characters into the episode?  
_{which kinda paints them as incompetent writers, but who cares}

This is indeed what will happen.