NAT behaviour with multiple NAT IPs

[adamw]

Hello,

Yesterday I accidentally added a second host to a rule thinking that only outgoing traffic would be affected.
What happened was also incoming traffic was allowed as well a second IP being added to a NAT Port Forward rule.

From my brief observation traffic was reaching both destinations in a round robin fashion.
Is that what's expected?
Does pfSense apply any kind of prioritisation or any other logic in decision making?
I.e. where to direct to when a new incoming request arrives?

pfSense version 2.2.6.

Thanks
Adam