Green’s Dictionary of Slang

(Aus.) a bad temper.

1918		Cairns Post 12 Mar. 7/5: S.O.L.-Delete. Applied to any- thing that cannot be done or is called off. Signallers' alphabet.
1951		D. Stivens Jimmy Brockett 137: I had a bit of S.O.L. the other day, but I hope you’ll lay off my wife.
1993		Aus. Word Map 🌐 S.O.L. shit-on-the-liver. A bad tempered, moody, sulky person was said to have S.O.L.