If this turns out to be erroneous, does anyone know what happens here? I assume that if it is clear error then the licensing won't be valid and they can revoke it?
>Subject to the terms and conditions of this License, each Contributor hereby grants to You a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare Derivative Works of, publicly display, publicly perform, sublicense, and distribute the Work and such Derivative Works in Source or Object form.
It is worth pointing out that this is only relevant if 1) they have the rights to it in the first place, which is not a given, and 2) a judge finds that someone trying to take advantage of the error is in the right, which is certainly not a given depending on jurisdiction - a long list of considerations might affect whether you could safely depend on the original license.
In this case it appears the copyright to the fonts is held by Commercial Type / Schartzco Inc., not The Guardian, and so they quite possibly don't have the authority to put them under the Apache license in the first place, making the license moot.
That's a circular argument, you can't appeal to clauses in that license to determine if that license is valid. If they can withdraw the license then that clause is also withdrawn.
I don't know about copyright law but in contract law just because something is written in a contract doesn't make it automatically applicable.
An analogous situation may apply here where this can be considered a misapplication and so the license does not apply.
Either way I'd not use this licence to comply with "don't be a dick". Not being an ass here may encourage future releases, being an ass over this could lead to "this is why we can't have nice things.".