Non-anonymous single-hop HS enabled tor doesn't detect already existing anonymous, HS at start-up

While trying to configure a toy non-anonymous single-hop onion service I ran into something that I believe is a bug.

The torrc that I reused from an earlier experiment already contained a HS configuration entry created in anonymous mode. When I enabled HiddenServiceSingleHopMode and HiddenServiceNonAnonymousMode and started up tor everything started up correctly and I was able to reach the configured HS service correctly. But when I sent the tor process a SIGHUP tor exited with the following error:

Nov 11 17:40:06.000 [notice] Read configuration file "/Users/ahf/torrc".
Nov 11 17:40:06.000 [notice] HiddenServiceSingleHopMode is enabled; disabling UseEntryGuards.
Nov 11 17:40:06.000 [warn] We are configured with HiddenServiceNonAnonymousMode 1, but one or more hidden service keys were created in an anonymous mode. This is not allowed.
Nov 11 17:40:06.000 [err] Reading config failed--see warnings above. For usage, try -h.
Nov 11 17:40:06.000 [warn] Restart failed (config error?). Exiting.

Steps to reproduce:

  1. Create a anonymous HS in the torrc.
  2. Start tor to make it create the keys for the HS.
  3. Stop tor.
  4. Enable HiddenServiceSingleHopMode and HiddenServiceNonAnonymousMode
  5. Start tor (which will start without problems).
  6. Send tor a SIGHUP which will cause it to exit with an error listed above.

I would expect tor to exit when starting up and not when it's re-reading its configuration file.

I've been able to reproduce this with the 0.2.9.5-alpha Debian package and with Git HEAD (0980787f91cfc420) on the master branch.