Stats serialization/deserialization mismatch causing graph progress not to be shown

If a slave has no disk parts to process, then it is sending back serialized progress stats about subfiles (0)., that the master is not expecting, consequently causing the serialization/deserialization to go out of sync and cause unexpected results. e.g. errors like:

00001511 PRG PRO 2022-08-19 10:16:51.185 9 80 W20220819-100855 "Failed to find activity, during progress deserialization, id=0 - graph(graph1, 407)"
00001512 PRG PRO 2022-08-19 10:16:51.185 9 80 W20220819-100855 "heartbeat error in graph 407"