THIS IS FOR THE NON-EX POLICE 1300's
Being a newbie to this site my apology before I start as everybody might already know this method but, whenever I know that I want use the panniers without them being locked.
I place the key into the lock and turn to unlock, lift up handles, lightly press and hold down the spring finger at the bottom of the slot, turn the key into the lock position then, with the latch over the spring remove the key and close the handles.
The panniers will remain unlocked until you want to lock them. Then just place the key into the lock and turn it to the unlock position and then turn it to lock it.
This method does not allow the locking latch to enter the slot in the handle to lock but the pannier lid is locked at the top with an independent locking mechanism.
It seems to work okay for me, but I might be missing something.