Dear Chris,
I have build a similar setup, but was unable to reproduce the problem. Both after a system restart and after 20+ min. the IOCore responds fine. What I did see is that you are using an older firmware version, could you please upgrade to the newest version? (If you download the newest version of the vManager the firmware is included) If this does not solve the problem, could you use another tool to verify that the message is indeed not sent out? (If you are looking for a tool, you can use the monitor of Cueluxpro). My setup was build using firmware version 1.36 and I used Cueluxpro for OSC message monitoring.
Hope this helps,
Best regards
Jurrien