More signs Russian armour stocks are getting low.
Increasing amounts of T-62M/MV being destroyed or captured by Ukraine. At least 30 in the past month (Oryx literally can't keep pace with the reports)
T-72As have been reported as being transported out of storage depots for deployment to the central Donestk area (the last one of those was manufactured in 1984 or 1985).
T-72s (yes, not even T-72As, just plain old T-72s) and T-72Bs reported being transferred from Belarus back to Russia. Belarus got 70+ T-72B3s from Russia in the immediate pre-war and early war period. There is speculation these may just be going back to Russia for upgrades, but it's not like Russia has a whole lot of spare capacity when it comes to repairing/upgrading tanks for foreign nations at the moment.
I also think I found a good answer to why so many T-62s are being seen in Ukraine (seemingly in preference to the thousands of T-64s, T-72s and T-80s that are reportedly still in storage).
When the T-62 was declared obsolete against western tanks in the late 1970s, use was transferred to second line commands, mostly in the Far East. These units don't train as much as first line units with T-72s/T-80s so their tanks didn't get that worn out. And the harsh weather in these regions meant that a lot of tanks were stored indoors.
These T-62s were also in more recent use - some second line units were still officially operating T-62s until as late as 2012, and were mothballed after that. The T-62 is also reportedly simpler/faster to restore from storage to service, less fuel hungry than the third generation tanks and has a smaller overall logistics trail. So it got preference over the newer tanks when reactivations occurred for lower intensity conflicts like Chechnya and Georgia. Which meant that the tanks were being kept up to date for second line use - as many as 900 were modified to the latest T-62M or MV standard prior to 2012.
So, there's a pool of (somewhat) modernised, well stored and reasonably maintained T-62s in storage. They're easier to put back into service, less logistics heavy and while the gun/armour/sighting systems is not up to moderns standards, they're considered "good enough" to support infantry and act as ersatz artillery/assault guns.