Knowledge of these particular bayonets is not one of my strong points but that bayo might be an early one. I don't see a drain hole in the pommel.
Looks like a nice brown Aussie scabbard, one of those Mangrovite, or is it Vegemite ones? There will be a date embossed into the leather beside the seam on the back.
Some early bayos originally had a hooked quillion. Designed as a blade trap to capture the blade of a bayonet fencing opponent, in the trenches it was found that the hooks were dangerous in that they could get snarled up when trying to cross through barbed wire. Not good when one was in a hurry.
The factory dropped the feature at manufacture and the existing ones in service were recalled to have the hook portion removed. A drain hole was drilled as part of the upgrade. But I see no drain hole on that one.
I might have it all wrong, and it might just be a common P1907. But well worth checking out to read the markings on the ricasso.
It looks like it would clean up nicely.