My baby goes psycho at 7pm every night (colic?)

I’d assumed it was just our child, googling set hour baby psychosis kept returning useless results, and for a while we thought we were alone with our prime-time psychopath baby, but a couple of days ago one of the parents of Baby M’s daycare-mates mentioned that their baby goes psycho at 7pm every night also.
My original belief was that perhaps it had something to do with coming back from daycare and being both riled up and down by the trip, but it doesn’t seem to matter what day it is, whether or not daycare was involved, light levels, ambient temperature, humidity, how much she’s slept, or what, my baby goes psycho at 7pm nearly every night.
We’ve managed to delay the beast sometimes by a few minutes, there have been times that we managed to distract her almost till 8pm, but the fury can be seen around the edges of her eyes and eventually the demon walks, or actually dissolves into a pool of tears, until we finally manage to do a diaper change and then swaddle her.
After the prime-time demon goes, she can be unswaddled, but the psycho baby that is our prime-time freakout machine cannot be swayed by much of anything.
This has lead to people seeing Baby M as a little monster as from 7-9 she’s something you have to manage freakout levels on.
Tonight, we managed to keep her mostly held at bay while we ate with some friends… she seemed to alternately want to be held by everyone and also desired the skill to grab a knife and plunge it through our hearts. We got her home shortly after dinner, a car ride filled with screaming that refused to be soothed even with ITMama sitting in the back seat.
The meltdown had lasted nearly an hour by the time we got her hogtied and put down, and within maybe two minutes of being unable to flail her arms around, she looked around with one final “fuck you world,” looked at me with the stated desire to be given her baby cork, once given she shrugged as if to say “whatever, I’ll be back…” sighed once, and went to sleep.
Her fury left a blotchy tear-streaked face which subsided in about another minute and a half when she passed out, no detectable demon baby left.
I used to dislike her from 2am-5am, this was a three hour window in which she was the demon, but I think she’s decided she can get maximum exposure at 7… the main thing I want to know is how does this baby always know when it’s 7pm? Oh yeah, and how the hell do I stop the demon child?
Anyone else out there with a daily freakout at the same time every day? We’ve altered her feeding, sleep, everything, and I think she’s only missed one freakout window in the past month. It’s insane.

The closest thing I can find on the internet appears to be colic. Unfortunately, as I’ve learned, colic means something is wrong and you don’t know what it is. This is one of the reasons everything that claims it soothes or aids colic is generally full of shit, if you don’t know what the problem is you’re just eliminating one potential cause thereof.
One of the interesting things I learned while researching colic is that babies generally cry two hours a day, with colic being defined as three or more, meaning Baby M is a saint in comparison.
Eh, weird times. Colic is listed as a leading relationship stressor also.