ShortestPathTree with new virtual nodes as "destinations"

Hi all,

I’m using ShortestPathTree to get some isochrone-like outputs from a set of reference points.

For each of my reference points (which are usually located part-way along a Way), I can get a list of all of the graph nodes which are within my travel time limit using a ShortestPathTree.

What I would love is to get all of my reference points which are within the travel time limit of each of my reference points. Is it possible to include snapped/virtual nodes in the results of ShortestPathTree? If so, can someone point me where to start? Do I need to create a QueryGraph with all of my reference points added in somehow?

At the moment I’m manually adding on the final few metres or so from the node to my reference point, which feels clunky and is slowing things down. Any pointers would be great.