CH and updating edge VehicleSpeed

Hello,
I am using GH 7.0 and about to upgrade to 8.0 and wanted to make some changes, but first I have a question.

If I upgrade the speeds of some edges, can I continue to use Contraction Hierarchies during the import phase?

...
if(snap.isValid()) {
	EdgeIteratorState  edge  =  snap.getClosestEdge();
	DecimalEncodedValue  avgSpeedEnc  =  graphHopper.getEncodingManager().getDecimalEncodedValue(VehicleSpeed.key("car"));
	edge.set(avgSpeedEnc, newSpeed); // Adjust the speed
}
...

Thank you

Any change to the graph needs to happen before CH preparation. A change afterwards is not considered and will lead to problems. (This behaviour was the case since we have CH.)