Mr. T (MrT4) said:

But my bet for the T54/55 are to be used as parts donors for the T62M modernization contract. T55 and T62 share many parts production of which mostly ceased in 1974 !

I disagree.
The T62 is quite a rare tank by comparison. It has not been widely exported. The T55 on the other hand is the most produced tank in history. Its in use all over the world. Production of spares and ammo is up and running. Maybe not in Russia but certainly in China.
The use of T55 is most likely because its possible to quickly get the needed spares and supplies. Which is not the case or if only to a much lower degree with the T62. Ironically the T72 is hard to support as well. Its out of production. Parts for the modernised versions are much harder to get and China neither uses nor supports this system.
In addition it makes little difference. If tanks are mostly used as long range fire support the advantages of a T62 or T72 over a T55 are limited.
Most likely a T55 with thermal imager would be more usefull than a T72 without.

2 tanks per shift, 3 shifts per day, 5 day week= 30 per week x 48 weeks  ( 4 weeks off for factory maintenance) = 1,440 refurbished tanks, so pretty close.

That is the whole point T55 is AK47 of tank world and plentiful around the world,but not in Russia , Having spare parts available throughout the world hardly matters, and in all practical terms T62 has a huge parts commonality with T55 , practically compete drivetrain,From what i can read in Russian forums, T55 stock is near non existant (some sources claim less than 300in total) as is T55 100mm ammo in comparison to 115mm. (Note tanks on the train are actualy T54 so pre-nuclear, as such possibly virgin stock.

T62 is rare outside Russia but vastly outnumbers T55 stocks in Russia,T62 was constantly rebuilt and upgraded in the Soviet Union trough 80's and 90s while the T55 stocks were not  ,T62 has superseded T55 since 105mm canon became NATO mainstay. T62M was also being upgraded in numbers for Syria , last order for modernization of T62MV was issued in 2021. pre Ukraine war , they did not bother with T55 , Up to 1991 T62 was kept as a Reserve type , was used in Afghan ,Chechen and Georgian wars so its quite obvious its the 'ersatz' tank since ever.

And like said we know of a contract for 800 T62 to be rebuilt to T62M, and none in regards to T54/55 , so till there is some more data besides a photo on the railcar its hard to deduce much else.

Also remember 7 main factories produce 52 or so different types of armored vehicles , while more than 20 repair plants can handle simple refits like T62M , its about adding 'production' capacity without actually producing the parts. Same as the German scrapyard that cut 500 or so pieces of armor per year , was cannibalizing useful parts all the time and those parts will now be used in any refurbishment programs.

And the end of the day Leopard1 being upgraded by the German industry fits the same mold and we hardly see ridiculing articles about 60y old tanks being refurbished for Ukraine, instead we are seeing articles about modern western tanks for Ukraine.

gatnerd said:

I've thought a few times that a modern version, based either as a stealth drone or big cruise missile / glide munition, would be worth pursuing.

You mean like this:
 

YouTube

Deutsche Aerospace Dws-39

A new generation air to ground area (cluster bomb)

The follow up developments of MW-1 where killed by the cluster munitions ban as well.

Yes similar to that or the JSOW, but larger sized to replicate the payload of MW-1.

Very interesting list of supplies requested for a drone unit in UA:

https://www.ar15.com/forums/General/OFFICIAL-Russo-Ukrainian-War-/5-2499714/?page=3779#i103448452

Many components suggest use in DIY munitions, such as a request for 2000kg of 3-6mm steel balls, or 4mm laser cut shrapnel. 25mm thinwall pipe also seems like the core for a VOG type DIY banger.

Shahed needs to be painted with 4th fighter downed, seems Shaheds are the real Ghost of Kiev 

Was kinda expected given the relatively thin armoring of a baseline A4 ,APU is installing the Russian "Kontakt-1" 

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A Ukrainian combatant from the TDF 127th Kharkiv Brigade with a very interesting modded AK-74 - complete with mag w... https://t.co/xCMKpANtQN

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NLAW ACOG repurposed as AK sight

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