Hugh Jarse,
Could be the QL fleet didn't get the full beta lockout system. This is from the 300 manual,
Beta Lockout System (CR 873CH00011)
This system incorporates electrical circuits to prevent the propellers from entering the ground Beta range of operation during flight.
...
The BLS is disabled on the ground to allow for discing, by either 50 ft. RAD ALT or WOW signal ... Setting the PLA [Power Lever Angle] less than Flight Idle while in the flight mode enables the system. Beta backup protection remains enabled regardless of PLA setting while in the air mode.
The warning horn provides an aural warning [canaries] as the Flight Idle gate is removed by lifting the power lever triggers, and before ground beta is actually selected. The revised beta backup enable logic provides low blade angle protection independent of PLA while airborne, instead of the existing standard PLA greater than Flight Idle logic. The NP trigger is tripped upon detection of NP values in excess of 1000 PROP RPM when the power levers are set below the FLT IDLE gate in flight. This provides a discrete signal to increase the prop blade angle to reduce PROP RPM to values below the trigger point.
(My comments in square brackets [].) So it physically stops the props from going into beta as well as having the warning chirps when you lift the triggers. Incidentally it is not mentioned in the FCOM manual, but is in the Flight Manual. My reading of it is that if you have the canaries then you have the rest of it. It's not something you'll be testing in flight though and it's disabled below 50' RADALT so you wouldn't notice anything different in the flare.
If you had Beta Lockout Test switches on the Captain's side panel then you had the revised system that prevents beta in flight, if you had Beta Backup Test switches then you had the original system.