Consistency only holds for the period of time of the minimum mirror validity window.
This is, a pessimistic take, but maybe not the most pessimistic. In addition, you can't make guarantees about future or past consistency. That is, you could be at the start of a validity window (such that consistency holds into the future), at the end (such that consistency holds into the past), or anywhere in between.
If you have multiple mirrors, you might be able to get consistency for the minimum window into the past and into the future, but you can't bank on that either.
This is, a pessimistic take, but maybe not the most pessimistic. In addition, you can't make guarantees about future or past consistency. That is, you could be at the start of a validity window (such that consistency holds into the future), at the end (such that consistency holds into the past), or anywhere in between.
If you have multiple mirrors, you might be able to get consistency for the minimum window into the past and into the future, but you can't bank on that either.