Why is my API quota not resetting after UTC reset?

According to How API Keys Work, nan default regular API limit -- which is per site, per time -- is 300.

I started pinch 300, arsenic expected, but complete a play of days, I've noticed that nan remaining quota has now been whittled down to astir 70 something:

{ "items": [ { "user_id":0000,"display_name":"abc","account_id":00000 } ], "quota_remaining":70,"quota_max":300,"has_more":false };

Even aft nan UTC reset today, nan quota remaining is still nan same. Is this a 1 clip point wherever erstwhile I usage each of this up, that's it, I'm done for good, aliases is this a bug?

What's more, this doesn't successful truth look to beryllium counting per-site, arsenic I tin alteration nan tract query parameter to immoderate tract connected nan network, and nan count still decreases, arsenic if this is not successful truth measured per site, but instead, network-wide:

https://api.stackexchange.com/2.1/users?order=desc&sort=reputation&inname=abc&site=serverfault&filter=!*MxJcsxUhQG*kL8D&callback=test

As an aside, I don't judge I'll request an API key, since nan app I'm building makes requests connected behalf of each individual user, and since I really don't image ever hitting nan 300 regular headdress since I'm caching nan information successful chrome.storage.local.

This assumes, of course, that nan 300 headdress is successful truth a regular headdress and not a life cap. Otherwise, my users would beryllium capable to usage this for a constricted time, until their ain life quotas person been exceeded.

Is this a bug, aliases americium I going to request to usage moreover heavier caching, for illustration penning information to a record connected nan users' filesystems? (euuuuughh - shivers astatine nan thought...)

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Two days later, I checked my quota again by hitting nan API. It now says 299 retired of 300, truthful it looks for illustration it's been reset. It's presently Nov 8, 7:38 AM UTC, truthful I'll hold until it rolls complete again and do different test.

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It's now presently Nov 9, 6:25 AM UTC, and I conscionable deed nan API for nan first clip since my past edit, and I person 297 retired of 300 remaining. Is this a bug, aliases does nan quota not reset each 24 hours arsenic documented?

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Today is Nov 10, 4:08 AM UTC, and hitting nan API coming results successful a refreshed quota. It does reset, but it doesn't look to beryllium resetting each 24 hours astatine 12:00 AM UTC.