Fortunately, according to the Department of Foreign Affairs (DFTA) and Trade, it looks like he’ll be spared corporeal punishment.

Griffiths was arrested under Singapore’s “outrage of modesty” law. Apparently, he got into an altercation with another passenger, whose seat he accidentally jostled when standing up to let someone pass to use to the bathroom. The other passenger cursed at him, and Griffiths responded in kind. 

Though it sounds innocent enough, another passenger on the plane says Griffiths has been drinking and acting unruly throughout the flight. By some accounts, his behavior was so disruptive, cabin crew were forced to intervene. 
Though the DFTA have not released details of Griffiths sentence, it sounds like he’s getting off light. In Singapore, “outrage of modesty” can be punishable by a two-year jail term, a fine, or 24 lashes with a cane.