Polycom SIP 2.2.2 Manual page 241

Miscellaneous Administrative Tasks
- end of sub-options
For the BootROM, sub-option 4 and sub-option 5 will contain the same string.
The string is formatted as follows:
<apptype>/<buildid>/<date+time>
where:
<apptype> can be 'BR' (BootROM) or 'SIP' (SIP Application)
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