Where I am operating from there is a switch that changes the PAL system from the 30 minute cycle to permanently on. If I have a night flight or know that I will be returning after dark I turn it to the permanent setting. That way, with the standby power generator, I don't have any alternate worries due to lighting.
I would have thought that Launie, and for that matter any port where RPT is operating after tower hours, would have had something similar and that the agent could be shown how to use the thing.
If that transgresses some security thingy then why not do what Alice Springs does and leave em on all night.