What does the /B suffix signify?

I believe that a /B (or /b) suffix to a callsign refers to the station being a beacon - perhaps in some instances it refers to temporary beacons set up for special events such as field days. It does not appear to be an official ITU or IARU designation or requirement. In Australia, beacons have an R suffix eg VK4RXX

Tim R VK4YEH

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