Thanks both - I was specifically looking for what the abbreviations might mean:
RO I suspect is recruitment office - Is there a list of recruitment offices anywhere - I suspect he then was going to 86 FS (Flying Squadron) but this changed to 30 FDS? (18/07/1918) where he remained until 12/06/19 - then what is 1 Concen Group / 1 Con Group between 12th and 14th June 1919 (It would appear to be some form of transfer) as he then ended up in Rein Park/ Rein Depot (which I have now learnt is a reinforcement depot)
So any details on where I might find recruitment office details or what the 1 Concen Group/ 1 Con Group reference might refer to would be appreciated.