Good news is that ZHA has changed the way they handle OTAs so we will be implementing the new method soon (probably in the next HA release). Also good news, the changes made to how ZHA handles updates has also made manual updates much easier. You can just add this to your configuration if you have a recent release of HA:
zha:
zigpy_config:
ota:
z2m_remote_index: https://inov.li/omega/firmware-zha.json
I don’t recommend doing this yet though because there is a fingerprint change in the latest firmware that requires a change that will probably be in the May release of HA: