This is a major and VERY annoying bug.
Under some conditions (I'm not totally sure what), TLs 9 and 10 jumpship autofacs will try to produce huge numbers of graviton launchers for at least one and possibly several watches. Industry gets allocated to ~ 25,500% for graviton launchers, so I suspect some sort of overflow/underflow is involved. The bug seems to only occur if no yard is demanding graviton launchers from the autofac. Once the bug starts triggering it tends to continue to recur every so often (usually multiple times per period.)
The industry over-allocation pulls in huge amounts of hexacarbide, chronimium and trillum through trade routes. On the subsequent cycle, all industry on the affected planet tends to get reallocated to extraction structures, completely shutting down the autofac for a few watches.
This bug severely messes with production, accumulates a giant surplus of resources and/or graviton launchers on the autofac planet, creates additional resource surpluses on any supplying hubs, and induces resource shortages in other parts of the empire.
If the autofac is getting trillum from a hub or extractor that also supplies trillum to hazardous-type worlds, it can sometimes trigger lethal survival goods shortages on these planets by monopolizing the entire trillum supply (this is most common with consumer goods autofacs on hazardous worlds, as explained in another bug report).