Try Show call-manager-fallback

If you mean bulk subscription you can use BAT. Update phones option,But if you mean Ip Phone subscribing to services during the Auto-Registrationprocess it is not possible.

Alias will work like a charm, but remember you can have only 10 alias commands with the same number.alias tag number-pattern to alternate-number [preference preference-value] [huntstop](tag—Identifier for alias rule range. The range is from 1 to 10)-...

You can use BAT.Update Phone: You can choose to update only the settings you want to change.Hope this helps.-K

HAve you tried disabling the RIS Data Collector Service.-K