If you've got three pickups with three volume controls, why do you need three on/off switches!?
Surely they are the pickup selector on/off switches?....These will give 7 possible pickup combinations: 3x single, 3x double and all 3 together...You can then experiment and dial in interesting tone settings and volume ratios, with the separate volume and tone controls for each pickup = a wide range of great tone possibilities....unique sounds abound, one would think.
I didn't take into account they could be coil taps.
Just be careful that you don't switch them all off if you're playing a gig......that was a fault of the lovely, if somewhat rare, Gibson ES-220
Personally I find this Airline guitar a little too cluttered with knobs and switches. Can't beat a Fender Telcaster for control simplicity.