(comment editor on Stonehenge page won't load, subject probably suited for general discussion)
As SlyCooperFan1 commented, the size of the continent of Usea increased significantly between AC 4 and AC 5.
Using the only other Strangereal landmass on the old AC 4 map whose proportions remained unchanged (i.e. the southern part of Osea with Leasath and Aurelia) I calculated a Usea size increase of approx. 255%.
The original Stonehenge asteroid interception radius figure for AC 4 was "1,200 km", but x 255% the radius figure would me more like 3,000 km which also looked compatible with a map I found where the Strangereal continents were added over the continents of a real world map (where Wellow and the western parts of Verusa match Greenland and Europe).
IMHO, the original AC 4 Stonehenge radius figure (and the one providing the distance between North Point and Anderson Crater on Newfield Island) is in need of revision or alteration to match the Strangereal world map from AC 5 onwards.
"Stonehenge's firing range encompassed a radius of 1,200 kilometers" should read "Stonehenge's firing range encompassed a radius exceeding 1,200 kilometers" OR "Stonehenge's firing range encompassed a radius ranging from Farbanti (west) to Snider's Top (north) to the eastern regions of Faith Park (east) and to Skully Island (south)"