What Happens If Russia Shuts The Door On Their Leaky ISS Module?

Russia is reportedly planning to permanently seal off the Transfer Chamber (PrK) of the Zvezda ISS module rather than continue attempting repairs on persistent air leaks that have been venting the station's atmosphere for years. The PrK connects Zvezda's rear docking port to the rest of the module, and closing it permanently would stop the leaks but sacrifice crew and cargo access through that port. Fluid transfers (water, oxygen, propellants) via external plumbing would still be possible. The main concern is reboost maneuvers — Progress spacecraft normally push the ISS from that rear port, and if the structure is deemed too compromised, the US side (via a modified Cargo Dragon) would need to take over. This approach was partially used before, but a permanent closure would be a new step for the aging station's final years.