Okey so I have the 20 bloodreavers from the starter box and I got the new box of 20 bloodreavers I now have a model count of

2 Chieftains
2 Hornblowers
2 Icon Bearers

17 Reaver Blades
17 Meatripper axe

Now reading the part in Description
A unit of Bloodreavers has 10 or more models. Some units of bloodreavers fight with reaver Blades, while others prefer to use Meatrippers Axes.

As looking on the GW website via the pictures a unit can consist of mixing and matching them and looking at the models of the chieftain hornblower and icon bearer they cant use meatripper axes so if you can olny have one or the other you could never have the chieftain hornblower and icon bearer with them.

So my question is can I mix and match the weapon types within the unit? (yes my army is clan based hence the names)
E.g

Clan of Khornes Madness
1 chieftain
1 hornblower
1 Icon Bearer
5 Reaver blades
12 Meatripper axe

Clan of Khornes Prowess
1 chieftain
1 hornblower
1 Icon bearer
12 Reaver blades
5 Meatripper axe