That seems a really unfortunate way to handle congestion, I understand there’s practicalities that outweigh convienience and at the end of the day the service is gratis, but at times the store/CDN seems to play up in ways that give off some bad impressions, straight up denying requests by not responding to them at all seems unfortunate, but then if the alternative is staggeringly slow downloads, maybe it’s better overall.
I’m unsure if this is entirely related to the LXD specific congestion control, but last night I was helping an upstream project with their snap, and the gnome extension SDK snaps were throttling so hard the builds were impractical. When the resulting snap was finally created, it was pushed to a branch release and the test user couldn’t even download it. 99% of the time the store is reliable but it feels like every so often it just acts up, in this case, for a matter of hours, world wide.
It feels bad saying it while knowing I’m paying nothing and I’m probably a significant burden on these resources even by myself, but I think at least saying it is probably worthwhile just to voice the opinion. (Also thanks for the free hosting 
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