RedHat and Ubuntu has kernel hot-patching. That's a case with binaries.

You're conflating runtime patching with continuing development.

Post training directly evolves existing model weights using the same optimization process that created them.

Software: source code -> compiler -> binary

Models: weights + training data + optimizer -> updated weights

Ie. binary is output of the development process.

Model weights are both – it's output and it's direct input for further development.

Model weight snapshots are continuously used all the time in this iterative process from the very beginning, being output of current step and input to the next step.