Does GH read the graph data file exactly once on load?

I am creating a Graphhopper instance with

new GraphHopperOSM().load(graphDataPath);

The graph data is dynamically collected from some URL. I have to delete graphDataPath when it is not required anymore. If GH reads the graph data path exactly once I can do

fetchGraphData(url, graphDataPath);
new GraphHopperOSM().load(graphDataPath);

Is this safe or might GH read some of the files in graph data path multiple times?