[HWR_14]

So I allocate my one BTC to lightning network A, so I can spend it there. I try to spend it on lightning network B and it rejects the spend because it's allocated to A in the main blockchain, even if I never spent it on A. There exists some mechanism for me to switch my bitcoin to B (by broadcasting on the main chain)... maybe? But then A needs to sign off that I don't have pending transactions?

[jenadine]

Normally, network A and network B would be connected by a path, so your bitcoins can be routed through the destination by moving balances of each intermediaries. If there is no route to the destination, you can't send them as is. You'd need to take the bitcoin out of network A and open a channel with B. And that's operations on the main chain so it may take some time.