You only need to swap two out of the three.
Think of it this way. Draw "A" "B" "C" around a circle. The correct sequence to move forward is ABC, or BCA, or CAB. Doesn't matter where you start as long as you get that order.
Now imagine if ANY of the wires were out of sequence. What's the possibility? If it went A -> C then the only next possibility is B - which creates the sequence ACB - which you will notice is one position rotated from CBA - or the exact reverse of what you want. Again, it doesn't matter where you start. If it was B, then you'd go to A then C - again, exactly reverse. Thats why if it's going in reverse, you can swap any two wires around, it doesn't matter which, and you will get a right combination. The controller doesn't care if you are starting at "A" "B" or "C", it just needs them in the right order to make the wheels spin in the right direction.
There is no LiPo fire danger from swapping the wires around, as long as you don't short them. But then, that danger was present when you first installed the wires. Obviously do it with the system powered down (disconnect battery, twist throttle for a second to drain any remaining power).
eBike: Q100H on 16S with Phaserunner FOC Controller
eMotorscooter: Vectrix VX-1 on 36S
eCar: Mitsubishi Outlander PHEV... Waiting for warranty to expire
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After 5 builds, the best advice I can give, is start with high quality products. I prefer http://www.ebikes.ca