Exactly who put out the story that Putin was giving a speech this evening?

There was no speech. The New York Times has suspicions:

... There was no official explanation from the Kremlin about why the speech was delayed — or even that it had been planned at all. ...

Putin’s Address to Russia Delayed After Hours of Waiting - The New York Times (nytimes.com)

I'll bet Moon of Alabama's Bernhard is also suspicious.  He hasn't updated his post today announcing the speech, which I quoted in full earlier today at this blog. He did remark in the post's comment section:

Seems like the Putin speech will not happen or come much later than announced:

RT has deleted its tweet saying that Putin would address the nation at 20:00PM Moscow time

Posted by: b | Sep 20 2022 18:34 utc | 61

But where did RT get the initial information from?

As to whether there will be a speech tomorrow, the NYT is willing to play the fool:

... By late Tuesday evening in Moscow, some of the Russian media figures who had said that Mr. Putin’s speech was coming said it would now come on Wednesday instead.

“Get up by around 8,” Dmitri Smirnov, a pro-Kremlin journalist who covers Mr. Putin, cryptically wrote.

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