Is it normal for the brake pads to move enough to make a knocking noise when I brake in reverse? The same noise is heard again the first time I brake going forward after the reversing. The noise is only heard once, presumably the pads are moving in the calipers.

Not normal, but it is known for the pads to delaminate which might cause this.

Thanks for the quick response.

I had this issue many years ago when using a particular brand of brake pad (don’t remember which, possibly Halfords). Basically the backing plate must have been a fraction smaller than the manufactures specification so moved in the calliper when braking the first time after changing direction. Changed them for a ‘better’ brand and all was OK. Worth also checking the pad retaining springs. Gone:
2002 FL1 TD4 GS Zambezi Silver
2007 FL2 TD4 GS Izmir Blue

Sounds like your handbrake shoes are not adjusted properly. If they are not adjusted correctly the shoes can move a bit on their mountings and cause the noise you are hearing. Worth a look. John
07 HSE Narvick Black
Land Rover Series One
Triumph Rocket 111 (sadly gone!)

OP said nothing about applying the handbrake.

Could be movement of pads as others have said.

Could also be a bush or a ball-joint somewhere. FL2 HSE Auto Galway Green
Evoque SD4 Auto Blue.
FL1 HSE TD4 Manual Black - Gone.
RR Classic V8 EFI - Gone