Got this today:
Feb 13 22:02:49.000 [err] tor_assertion_failed_(): Bug: src/or/connection.c:5113: assert_connection_ok: Assertion (conn->type == CONN_TYPE_EXIT && conn->state == EXIT_CONN_STATE_RESOLVING) || connection_is_writing(conn) || conn->write_blocked_on_bw || (CONN_IS_EDGE(conn) && TO_EDGE_CONN(conn)->edge_blocked_on_circ) failed; aborting. (on Tor 0.3.3.2-alpha efc105716283bbdf)
Before I changed the config from
ExitRelay 1 IPv6Exit 1
to
#ExitRelay 1 #IPv6Exit 1
and a little bit later to
ExitRelay 0 IPv6Exit 0