Daniil Kvyat "stood down" by Toro Rosso.

Toro Rosso have announced that Daniil Kvyat has been stood down. He will be replaced by Pierre Gasly for the Malaysian GP this weekend and for the remaining races of the 2017 championship.
Was this always on the cards? Has the writing been on the wall since he got unceremoniously dumped from Red Bull and replaced by Max Verstappen?

"Daniil Kvyat has not shown his true potential so far this year" is what Franz Tost has said, and this pretty much speaks for itself. Kvyat has had a torrid time back in Red Bull's feeder team - outscored massively by his teammate Carlos Sainz 94-8.
He has become something of a figure of derision, nicknamed "Torpedo", after a series aggressive/careless manoeuvres resulted in collisions with not just other cars, but also taking out his own teammate.

So where to for Kvyat now? He may benefit from a short break from racing to just get his head in order. With only 6 races of the season left, he will have time to analyze his performance this year and perhaps get back into the simulator after Christmas.
With Carlos Sainz leaving Toro Rosso "on loan" to Renault next year, I doubt that Toro Rosso will be starting 2 new drivers. I think Kvyat will still have a seat on the team. But having already had the ignominy of being demoted from Red Bull, and now stood down from Toro Rosso, it's a question of whether or not he'll be able to mentally come back from that.

Daniil Kvyat Career Snapshot

• March 2014: F1 debut for Toro Rosso aged 19 at the Australian GP. Finished 9th to become youngest points-scorer in F1.
• October 2014: After finishing 15th in the championship, promoted to Red Bull as Sebastian Vettel's replacement for 2015.
• July 2015: Maiden podium after finishing second at the Hungarian GP becoming the second-youngest driver in F1 to get a podium place aged 21 years and 3 months.
• November 2015: Finished the season in 7th place with 95 points - 3 points ahead of teammate Daniel Ricciardo.
• May 2016: Red Bull announce that Max Verstappen will replace Daniil Kvyat at the Spanish GP after Kvyat was involved in incidents at the preceding two races in China and Russia. After the Russian GP, Kvyat came in for particularly heavy criticism from Vettel as well as teammate Ricciardo, and the team called the race "a disaster".
• October 2016: Toro Rosso renew contract with Kvyat for 2017 season.
• September 2017: Toro Rosso announce that Kvyat will be "stood down" for upcoming Malaysian GP in favor of Pierre Gasly and iterate that "This is not a case of goodbye for our Daniil, as he still remains part of the Red Bull Family."