Roboports automatically upgrade belts, splitters, underground belts, inserters, and assemblers within their reach.
Providing the player with new tools or adjusting the game interface, without fundamentally changing gameplay.
Augmented or new ways of transporting materials - belts, inserters, pipes!
Related to roboports and logistic robots.
Using AAI Loaders when the mod upgrades the tier, the whitelist/blacklist enablement is not retained, resulting in unfiltered exports on upgrade.
Interestingly the filtered item(s) are still saved, it's just that it's not enabled for blacklist/whitelist like prior to upgrade.
What happens if you use an upgrade planner to upgrade AAI loaders?
Internally, Belt Upgrader calls the upgrade planner, so this might be a bug within Factorio.
You are absolutely correct, I'll reach out on the AAI Loaders page instead :) thanks!