Hi Pumpkin and MaggieMay24, thank you for your prompt replies, as hard as the truth is.
Guys, another question just to confirm the visitor visa 600 allows multiple entries - it states; 'must not arrive after xxx date' and stay period 12 months from the date of each arrival' - does it mean that e.g. he will arrive and leaves before 12 months is up and arrives again before xxx date, therefore he can stay for a period of another 12 months - i.e. in total nearly 2 years? Thanks, again.