Thanks for the replies.
The answer I got back from AA was
Travel can be booked ahead of time, but it cannot be ticketed until the
miles are in your account.
I replied asking
I can book the ticket, which is then guaranteed to be issued, so long as
I acquire the necessary miles to 'purchase' it before the flight?
To which the 'answer' was
As long as you have the miles and there is availability, the ticket can
be issued.
.
So I'm still none the wiser (is it me

) as one uses the termed 'booked' which is what I want to do then the other says 'ticketed' which is what I'll do when I get the miles.
I can get the extra miles now from my partner, by gifting them, but hey that costs
I take it nobody has done this??
Thanks.