Firefishy put this time range in last night in the VSL in Fastly. I’m still not 100% positive if a force refresh (e.g. Ctl+F5, etc.) would help on “non www.osm.org” sites as the (general) VSL code is not known (which is understandable so it cannot be gamed easily).
Also this one here: Dirty tiles cached for 7 days · Issue #441 · openstreetmap/mod_tile · GitHub would help a lot.