Artefacts around edge of mesh after baking

Hello! I'm trying to bake using cages in Substance Painter. The plaster on the nose should have dots on it uniformly, right up to the edges, but the edge has artefacts on it instead. During the bake, this image briefly appears where the artefacts appear:

The UV of the high and low poly models are the same so I can't think of what could be causing this issue. I've tried both a flat cage just hovering over the plaster and an all encompassing cage surrounding it but neither have worked.

Any help would be very much appreciated! Thanks!