Too bad that Flagellant flails won't get the +2 bonus since it will be an ongoing fight.
That's one of the things that could still use an FAQ IMO. The only definition for 'first round of combat' we are given in the book is that 'first round of combat' is short for 'first round of combat fought following a charge'.
Now, if you are counting as charging when pursuing a FBIGO foe, I could see someone arguing they do get the bonus.
I kind of don't think that is intended, but I sure can't find anything stating that for sure in the rule book.
Let's not start another long thread on this but even the new FAQ leaves one contradiction. The same rule (p213) that states that the first round of combat is the round fought following a charge also states that you have to use the weapon chosen in the first round for the rest of the combat.
The rules state:
1) The first round of combat is the round fought following a charge
2) A model with multiple weapons must select one of them in the first round of combat and must use it for the reminder of the combat. This implies that if you can choose weapon it's the first round of combat)
3) Pursuits into FBIGO enemy counts as a charge
4) You can't change weapons in a combat continuing after FBIGO
This creates a contradiction that only GW can clear up
The fourth bullet point in the selecting weapons rule (p213) need to be changed so that
*The round fought following a charge is not always the first round of combat
OR
*You can't always choose weapons in the first round.
There is no way to clear up this by RAW so lets not have another endless discussion. I think that the best resolution is to delete '(i.e the round fought following a charge)' from p213 Then we can go back to the intuitive definition of first round that we have been using for 25years: The first round of combat is the first round a units fights in a combat.