I'm REALLY struggling with Tera Bug, Flash Fire, Bulk Up Ceruledges right now. It's super frustrating and I have no idea how in the hell I can beat it with my squad.

(Click the team for the PokePaste link)
The major problems is that assuming it's using the normal spread of Careful, 252 HP / 200 SpDef / 56 Speed, these things happen:
-Skeledirge can't do much to it. Torch Song is nullified by Flash Fire, and Shadow Ball doesn't do enough damage. If I commit to my Fairy Tera on it, then it just clicks Bitter Blade and outregens my damage output.
-Gren does nothing to it, just because of all of the special bulk and Tera-ing out of its Fire and Ghost typing.
-Tusk does literally nothing to it outside of smacking it ONCE with a Knock Off, then all the damage being negated by Bitter Blade. Rock Slide/Stone Miss on Tusk is too unreliable either due to not enough damage vs +1/+1 Bug Ceru, or lack of accuracy.
-Scizor dies. When Scizor comes in on the +1 Bug Ceruledge, Technician boosted Aerial Ace (which used to be Thief for the Dengo matchup) doesn't OHKO it. (67.2 - 79% vs +1/+1 Ceru)
-Corvi can't wall it because of Bitter Blade.
-Gastro can't touch it because of its bulk, and it just sets up on Gastro.
I'm seriously at a loss here. This is one of the few only sets that my team can't handle at all.