It's been low for months now. The reduction happens to correlate with no more armored vehicles disappearing from the old Soviet stockpiles. I.e. all that's left is useless scrap.

For the past few years there were regular articles about the stockpiles running out, but I guess that was either about specific locations or vehicle models. I haven't seen any such news articles for quite a while, I think it's because there's nothing new to report. Russia appears to be limited to what they have in active service and to new production.

They're pretty screwed, new production can't keep up with the demands of the frontline. And it won't become easier with Ukraine destroying Russia's finances/oil infrastructure and military complex one drone/cruise missile at a time.

No, they have more than 1000 tanks in use. However they realized a year ago that they can't get more and so every tank lost is gone for the remainder of the war. They have been forced to make hard decisions to not use them if the risk is high. This limits their usefulness but ensures they have them.

Many of the tanks left are not in Ukraine. They have a long border that needs tanks near just in case someone is stupid enough to attack them

You need fuel to drive a tank to the front line and that is a bit of a problem due to some smoking issues in Russia.