Stan Lee's cameos have become as much a part of the Marvel Cinematic Universe as Iron Man or Captain America. With the MCU working toward wrapping up Phase 3, we now know what Lee has planned for the next couple years worth of films. While recently making a comic-con appearance Max Anderson, Lee's personal manager, who appeared alongside the comic book veteran, revealed that Lee has filmed his cameos for nearly every film set for the next two years. According to Anderson...
Those five films make up the bulk of Marvel's remaining scheduled movies. The only Phase 3 film not mentioned is Captain Marvel, which has yet to begin filming. While it will release in between the next two Avengers movies, scheduling requirements for Avengers 4 actually have that movie shooting prior to Captain Marvel. Filming that cameo will likely be the next thing on the agenda, however, as we'd expect Captain Marvel will be looking to start filming by the end of the year, after Ant-Man and the Wasp and Avengers 4 have wrapped up.
And this is just with the official MCU movies. There's a pretty good chance Stan Lee has also filmed, or will be shortly filming, cameos in Deadpool 2 and X-Men: Dark Phoenix, which are both currently in production.
The announcement of Stan Lee's cameos at Wizard World Nashville (via ComicBook.com), show that the man still isn't slowing down, even at the age of 94. While his cameos aren't necessarily the busiest and most stressful job in the world, the guy has clearly earned a rest, but he obviously doesn't want it. Still, Stan Lee is 94. We have to accept that he won't be able to continue to appear in Marvel movies in perpetuity. The end of Phase 3 would certainly be a good place to put a bow on things, if he were so inclined, especially since he's already done the work for almost all of the entries
Having said that, the MCU's Phase 4 is probably further along than we think. While only the sequel to Spider-Man: Homecoming and Guardians of the Galaxy Vol. 3 have been officially announced, and only one of them has a release date, Marvel has said they don't want to take away from the conclusion of Phase 3, and thus won't be officially announcing much else until Avengers 4 is over. Once that happens, we'll probably see a lot of things shift into high gear, and that could include Stan Lee filming cameos. We know he films cameos for several films all at once, so it only takes a couple of days for Lee to become a major part of Phase 4.
We'll next see Stan Lee in some capacity in Thor: Ragnarok, which hits screens in November.