In the last 24 hours or so there was first a 5.2 at the south of the fault line beneath Orchid Island, then a 4.7 off the coast of Taitung, then a 4.3 in Hualien.

Looking at the terrain map, it appears the earthquake has had a knock-on effect up the fault line - this also appeared to be the scenario when we had the 5.3 in Taitung a few years ago

Seems to only work travelling up from the south to the north - there didn't seem to be any knock-on fracturing travelling south from the 3x6M's they had in Hualien in 2018