In a failover scenario simulated using the numberguess example, the Weld/WF integration code may throw:

javax.ejb.NoSuchEJBException: WFLYWELD0023: EJB has been removed

I haven't managed to reproduce this locally yet. It happened most likely because the containers in the test were started/stopped at wrong times (infrastructure problem, probably). However, when reproducing locally, even when the containers didn't have time to replicate state, I only managed to get an old value from the cache, but not the NoSuchEJBException.