Dusty Rhodes WWF departure in 91

When exactly in 1990, did Dusty give Vince his official notice he was leaving the WWF to return to WCW as booker?
Dusty's WWF character really changed right after Summerslam 90 when he began his feud with Ted Dibiase. He dropped the polka dots and went back to the more traditional "American Dream" that was in Crockett. It seemed the feud went from Dusty looking like he would beat Dibiase in the blowoff after a lengthy feud to the entire angle switching to Dibiase/Virgil issues by the time Survivor Series 90 came along, and by the Rumble tag match Dusty and Dustin were just the backdrop to Virgil turning face.
​I don't have the exact date handy but it was known well in advance, and given that the political tide had shifted 6 million times in WCW since his departure, it's no surprise that he'd be able to come back with open arms again.  Specifically, Ole Anderson was such a colossal disaster as booker that Dusty was pretty much able to walk right into the top job again.  Although this does lead to a funny Ole story, where later on he blamed Dusty Rhodes for booking the Black Scorpion blowoff with Flair, even though Dusty was still with the WWF for another two months at that point!​

The Postgame: Why Punk’s departure was possibly shrewder than even he knew, or: Why the clock is ticking until we turn on Daniel Bryan

Only professional wrestling’s modern-day revolutionary could be the cause of such seismic activity simply by taking a leave of absence.

Almost three years ago, CM Punk’s pipe bomb promo turned the WWE on its ear, gave us two months of memorable storylines and one of the greatest matches ever (two, depending on how strongly you feel about Punk and John Cena’s Summerslam rematch that some feel was superior in its technical proficiency). It didn’t cause the sea change in the business it promised, probably because it was just a wrestling angle and people expected way too much of it. It did cement Punk as one of the WWE’s made men, however, and his subsequently epic 434-day title reign tangentially facilitated the return of Paul Heyman, the debut of The Shield, and perhaps most importantly, “The Brad Maddox Experience.” 
Prior to walking out of the WWE on January 28, the previous two months of storylines appeared to have us heading for a Punk/Triple H Wrestlemania showdown. This reportedly wasn’t enough to keep Punk around a company he clearly needed a break from (and they, most likely, from him). 

Rumors at this time had Daniel Bryan’s list of one-on-one Wrestlemania opponents staying at one, in the form of a third match in four years with Sheamus. I guess going from not winning a meaningless toy the United States championshp in the pre-show to losing the Intercontinental belt, which for some reason was replaced years ago by the old WCW title belt the World Heavyweight championship in 18 seconds in the opener to going over the guy in the No. 5 match in the card would have been…something of a promotion, if one allows themselves to ignore how far past that perch Bryan has ascended between Wrestlemanias. 
Instead, Punk’s departure opened the door for Bryan’s promotion into a co-main event match with Triple H, and the WWE’s hilarious miscalculation of how fans would respond to Batista’s return was enough to necessitate also adding Bryan- though part of me would find it really funny how mad so many of us will be if a Triple H win keeps it from happening- to the WWE title match. 
The best we can do is take educated guesses as to how things would have shook out if Punk stuck around. One of the two probably still would have needed to be added to the title match, given the fan revolt on Batista’s Rumble win. 
Still, how things have actually played out have me wondering if the clock is already ticking on WWE fans turning on Daniel Bryan. 
It’s what we do. And we’re getting more efficient at it.
It took wrestling fans nearly a decade before they outright revolted on Hulk Hogan. Bret Hart was a top-flight, main event babyface for only five years before we favored foul-mouthed, despicable midcard heel Steve Austin over him, while the same happened to co-top face Shawn Michaels on the same 1996 Survivor Series show against Psycho Sid. We booed The Rock out of the building against Austin, Hogan and Brock Lesnar in his last two years as a full-timer. We started booing John Cena not even a year into his run as the top face, and we never stopped. 
This is, in large part, a function of just how many more hours that WWE is on TV than the WWF was. 434 days of Punk’s reign had his face on television and pay-per-view more than Hogan’s in one-third the time. 
It’s also a function of the WWE co-opting everything cool and counterculture that their fans originate. I guess we can’t blame them; we’re willfully living in their “Universe,” so we’re willfully ceding ownership of our customs and mores to them the moment we use them at their shows. CM Punk’s pipe bomb, Fandango-ing, Boo-tista….and now the “Yes! Movement.”
Daniel Bryan flooding the ring and ringside area with fans to bait Triple H into granting him not only a Wrestlemania match with The Game but a spot in the main event was, unequivocally, a classic Raw segment and possibly a WM30-saving moment. It was the Austin beer truck for the meta generation (and a PG show). 
But two days later, it feels more like an end than a beginning. OK, maybe that’s a bit maudlin, but those who were less than swept up in the euphoria Monday night to point out that it was another example of WWE co-opting the cool were onto something. This almost makes me think we should grudgingly give WWE creative a bit more credit: maybe they had the foresight to know the money was in the chase with Bryan, and they were putting off making him the top guy until they needed him to be. They know the history of fans turning on the top guy. 
This is no reason for Bryan to not be the top babyface and main event Wrestlemania. The cost of never pulling the trigger on him would have been immeasurably worse than the eventual souring of Bryan as the top guy will be, because the chase can’t last forever and the biggest show of the year is the best time for said chase to end for your top babyface.
And worrying what will happen down the road from a Bryan reign reminds me of a classic Mitch Hedberg quote, when asked if red wine gives him a headache: “Yeah, eventually. But the beginning and middle parts are amazing!” It’s a promising year with Bryan as The Man, even if we know roughly how it eventually ends.
But to bring this full circle, our other hero just might be waiting in the wings to fill that role when the fans decide it’s time for Bryan to either turn heel- like everyone but Cena has done after the fans soured on him as top babyface- or be cycled back down the card. This possibility likely had nothing to do with Punk’s decision to quit. But oh, does it make for some juicy possibilities. 
Punk will almost certainly be back. It’s funny, because so many fans wanted his 2011 absence after Money in the Bank to be prolonged to build the hype for his return with the “real” WWE championship. I never fully agreed with that, but maybe I was wrong. Because by leaving for real, even if he has no idea if or when he’s returning, he may have unwittingly sewn the seeds for his own ascension to the rarefied air Bryan’s currently reaching, air that Punk himself never quite reached.
As Daniel Bryan usurped the underdog darling role and took it to an even higher level, Punk got out before we got sick of him. 
He’s left Bryan to take that eventual hit solo, and as a result CM Punk could eventually rule the (WWE) Universe.