I'm finally a Major

[paulr]

LNO - he was a Liaison Officer ... or he's the Latvian National Orchestra .... take your pick.

NAVCENT - United States Naval Forces Central Command

UK Naval One Star - A Royal Navy Commodore

J3 - Current Operations

Simples

I had guessed most of that

The bits that I found particularly confusing were the N in LNO and the lane 

Interesting that the USN doesn't appear to have the rank of Commodore, instead splitting Read Admirals into two halves

[d_Guy]

Interesting that the USN doesn't appear to have the rank of Commodore, instead splitting Read Admirals into two halves

Splitting the rear into two halves was strangely evocative! 
Incidently I think we do still use Commodore as the curtesy title for the senior captain present, but could be wrong.

[d_Guy]

UK Naval One Star - next to lowest rank in the galley

good one Leman!

[Dave Fielder]

LNO ... Last National Objector
One Star ... I didn't do very well in McDonalds customer service
J3 ... Just Jumped Jauntily

[Orcs]

Congratulations Dave.