Bill,
On the XPression Gateway, there's a MOS Objects setting where you can define the format of the MOS Abstract. You can right click inside the Format box to see a list of all available fields to include. You can type your own hard-coded text in as well. In your your case, choose @CHANNEL@ and add the "XPN " yourself instead of using @VCNAME@ so you don't get the entire description of the channel in your MOS string.
Once you make the change on the gateway, relaunch your plugin and all new MOS items will use this format for the MOS abstract.

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Jeff Mayer
Ross Video
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