I would like to point out that the reference to the "Mebo 4 " was an idea that I passed onto Garry way back.
The reasoning behind it was that the original ship was Mebo (or Mebo 1) which was found to be too small.
We all know of the Mebo 2.
Then in 2000 there was an RSL of RNI from a boat that was renamed Mebo 3 for the duration of that RSL.
When Garry's re-incarnation of RNI hit the airwaves back in 2008 (yes it was that long ago), it seemed a natural progression to nickname the server Mebo 4.
Hence the jingle "She's back once more from the Mebo 4 ......"