Using LLMs to backport approved paches in upstream software into older versions should be significantly easier and more accurate than producing the original patch and reviewing it. In the backport scenario the knowledge that the patch is "good" is already settled. The source around it is in place so the LLM has very tightly bounded context to work with, left with very little freedom to make mistakes. I think LLMs will make LTS releases significantly easier to maintain.
Debian btw.