Pedant mode - a retired officer should NOT use the abbreviation Retd (or equivalent) after his name unless it would cause confusion within an organisation (for example, ex wg cdr now working within government with the equivalent status of a flt lt). However, a retired officer shall not be identified as Wg Cdr M Mouse RAF, he needs to bin the RAF bit. So, it is perfectly acceptable for a retired officer to call himself Wg Cdr W Mitty as long as he actually held the rank. There's a whole argument about use of rank however I can say, as a retired officer, it is
sometimes useful for people to know your 'form'.
Turning to your particular Walt, ask him what was his last tour and when.
Here's an interesting one - ex RAF senior officer who is now an RAFVR(T) fg off. What rank should he hold, and when.
