Miles and Companion Rewards together?

I've got a lot of miles in my account, and also have 2 companion rewards ready to use; is it possible to use miles to further reduce the cost of a flight or can the companion tickets only be used on their own?

I'm looking at the cheapest way to get Australia next year, for myself, mrs vizbiz and the two little vizbiz juniors. I imagine I could (dependent upon availability - and there is some) purchase 2 Y, B or L tickets and then add the two companion tickets - but my real question is is there anyway to improve on the cost if I can use miles as well (I've got about 200,000)?

Thanks.

[HighFlyer]

Companion tickets can only be used with qualifying revenue fares [:(] The upgrade vouchers provided with the MBNA VS credit card allowed you to upgrade reward bookings though.

What class do you wish to travel in? You can buy x2 L fares and use the two companion vouchers for the kids but you wont (technically) be able to upgrade the companion tickets out of Economy. You can upgrade the L fares if there is availability though.

Thanks,
Sarah

Dependant on the age of the kids, it might be cheaper to purchase one Y,B,L fare and use a companion voucher so that the two adults are ticketed.

Then book cheap fares for the kids.

Saving the miles and 2nd companion ticket for a later date.

**edit**

Didnt think at the time.

Purchase a Y,B,L + one companion voucher to cover the adults, then use the miles for the kids. 100,000 should be a free economy round trip to Oz.