Mysterious seat allocation in code share airlines

Today I decided to attempt to get our seats organised for the trip.  As feared, our flight is the dreaded code share with BA.  So of course the qantas people are powerless to tell us anything about it at all.  They will sell us tickets, but not know what kind of plane it is or in fact anything at all about it.  They cannot even provide me with the phone number of BA.

It seems that BA have this new rule which means that you can request seats more than 24 hours in advance ... if you pay £20.  Except that we seem to have been allocated seats without the fee.  No one can explain it, or tell me whether it is the fire escape row (Harry is obviously not used to economy travel any more so feels that he will be unable to sit in a 'normal' seat).  Mysteriously, the children are on a separate booking reference to Harry and I, this seems eccentric, but there are no reasons why this has been done.  It is just the way things are.

I am now gearing up to call BA and getting ready for them to tell me that as I am qantas customer, they will not be able to divulge any information at all to me.  I can expect to be put in special seats where no flight attendant will come, and there will be no in-flight entertainment for us. (the system will be broken for those 2 rows - this has happened to me before).

I am fairly sure that we will get on the plane on Friday night, but it is harder than you think.