Ok, I tried to copy Achavi and just replaced the overpass backend (as per @TrickyFoxy s example) as the public instance seems to be quite overloaded.
Please check if https://achavi.hopapi.net is working for you, e.g. achavi - Augmented OSM Change Viewer [attic]
The overpass backend instance used is currently only accessible via that achavi copy and computes areas once a day while otherwise it is run on minutely diffs (with global planet data).
And the main goal is not to use the overloaded public overpass instance.