Anti-time future
The anti-time future was a possible future encountered by Jean-Luc Picard of 2370, when Q transferred his consciousness to the body of his older self. According to Picard, the events of this future took place 25 years after his time-period.

In this future, the  had continued to serve as the flagship of the Federation for several decades after 2370, instead of being destroyed in 2371. About five years prior to the events Picard encountered, the ship was almost decommissioned until Admiral William T. Riker took interest in his old ship and made it his personal flagship. The ship was refitted with a third warp nacelle and other technologies such as a powerful phaser emitter and a cloaking device. 

Romulus remained intact and inhabited, instead of having been consumed by a supernova in 2387, but the Klingon Empire had conquered the Romulan Star Empire and the former capital world was experiencing an outbreak of Terrellian plague. Relations between the Klingons and the Federation had also deteriorated significantly.

Picard had stepped down as captain of the Enterprise to become an ambassador, before retiring to his vineyards on Earth, where Irumodic Syndrome had began to cause his mental pathways to deteriorate. He had married Beverly Crusher, but the couple had divorced. After the divorce, she had kept the Picard surname and taken command of the medical ship . The ship had been allowed by the Klingons to deliver medical supplies to the plague victims on Romulus. 

Worf and Riker were both interested in courting Deanna Troi, but neither did so because of the other person. Troi later died, and Worf and Riker became enemies for the next 20 years. Worf became a member of the Klingon High Council, but his position diminished and he was relegated to the governorship of a small Klingon colony on H'atoria.

Geordi La Forge eventually retired from Starfleet, married Leah Brahms and became the father of three children and an author. He took ocular implants to replace his VISOR. Data held the Lucasian Chair at Cambridge University. He had emotions, was able to use contractions, and had added a streak of gray to his hair.

This future was altered when Q interfered by transferring the consciousness of Picard from 2370 to the body of his older self. The Enterprises from three time periods created the anti-time eruption and were subsequently successful in collapsing the anomaly. When Picard's consciousness was returned to his 2370 self, he shared his experience of how the future was going to unfold with the crew. He caused them to make different life choices, which created a new future. ()

Appendices

Background information 
No specific year was given for the future events. La Forge however stated that it had been close to 25 years since the crew were all together on the Enterprise-D. The  used this statement as a basis of dating the events to 2395. However, this would be based on the assumption that the crew of the Enterprise-D disbanded concurrent with the end of TNG Season 7 in the original future timeline, although Picard seems to make the same assumption when he states in the present timeline "A lot can happen in twenty-five years." The episode's script also describes the characters as having aged twenty-five years.

According to comments by Michael and Denise Okuda in  the anti-time future should be considered as an alternative quantum reality.

The prime timeline events as they have been seen unfolding in the feature films and in Star Trek: Picard indicates a clear divergence from the future events depicted in "All Good Things...". After Picard had shared his knowledge of that future to the crew, the Enterprise-D was prematurely destroyed in 2371 in . Deanna Troi averted her death and eventually married Riker. Worf and Riker did not become enemies. Data died in 2379 while still in Starfleet service, as was seen in . Romulus was destroyed in 2387 as was seen in . Picard had not yet contracted Irumodic Syndrome as of 2399, though he was warned by Moritz Benayoun that he might yet develop one of a number of terminal neurological conditions in , and died as a consequence of his temporal lobe abnormality in .

The only events that weren't altered were the replacement of La Forge's VISOR with ocular implants in ; the commissioning of the Negh'Var warships by the Klingon Empire as seen in ; and Picard's eventual retirement to the vineyards of Château Picard, as seen in .

Apocrypha 

Apocryphal works depict some of the events of the anti-time future as still taking place.
The comic series Star Trek: Countdown portrayed Picard as the Federation ambassador to  in 2387, as well as Data being still alive, after he had been "reborn" through the memory transfer to his brother B-4.
"The Path to 2409" on the official Star Trek Online website states Beverly Crusher assumed the command of the  in 2385. The game also depicts the peace treaty between the Federation and the Klingon Empire being dissolved in 2399, and a few  starships have undergone the same refit depicted in the anti-time future.
 Anti-time future