The answer to this is two fold. After an exceptional amount of work, our new data granular data storage is ready for production. We've been writing to it for a few weeks, and will be turning on read functionality before the end of the year. This will provide the down to the minute resolution you're looking for.
At the same time, we're working on enhancements to our reports. The Service Level Agreement report will be able to give you more accurate details as is, and we'll be adding some more configuration options over the next few months. You'll also be able to get any of this data out from our API.
The length of time the data is stored is based on your current package, I recommend reaching out to your account manager (or using Chat with Engineer to get in touch) for your specific storage period.