>>This means that they were using the tank like an artillery piece. This is a very ineffective way to use tanks.
Particularly if that tank mounts a smoothbore gun - which the T-14 does. Those are great for sabot enclosed armor penetrators; accurate artillery at a distance, not so much.
I had thought the T-54/55 was going to be used for that role. Maybe they are. Those mount, I think, a 105mm rifled gun, and the RF seems to have stocks of that (but all probably past the 'use by' date - shelf stable explosives were invented *after* EOL of the T-55).