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If you can include two or more of BA's oneworld partners on the itinerary, and if the itinerary meets BA's requirements for a multi-carrier redemption, then yes, a multi-carrier redemption can offer very good value for your Avios. Note that redemption cost in Avios is based on the class of service of your itinerary's longest segment, so it's conceivable that you might be able to include some segments in F for the cost of a J redemption.

Your BA Avios can also be redeemed from a QR Privilege Club account by "linking" your BAC account to a QRPC account -- which might or might not offer better value for your Avios.

Edited to add: a BAC multi-carrier award redemption can only be booked by calling BA. But you should be able to check award-seat availability for each segment on ba.com before calling.