https://docs.postmarketos.org/policies-and-processes/development/ai-policy.html
postmarketOS bans contributions written either entirely or in part by LLMs, so your contributions would be disqualified under those policies.
The Linux kernel, as far as I'm aware, does not have these same policies, so if your changes were to be mainlined, then the Linux kernel changes would then trickle down to pmOS, but your userspace programs/services would still not be able to be accepted upstream, nor would any of the non-mainlined kernel changes.