Hey @wgarcia, I think I've got the issue you describe. pawlinski recently posted a workaround on the pine64 forums which worked for me.

"I also had problems with images with OTA. The solution was to upload the first OTA image to the microSD card:
https://ci.ubports.com/job/rootfs/job/rootfs-pinephone-systemimage/1/
Then naturally update via OTA. Now everything works fine."