I am sending my Parents to Europe in May. I had to look pretty darn hard to find seats for them using the base 'Saver Award'. It was possible - and I'm happy with the outcome - to find them F seats from SFO to VIE. But I did have to split them up on two separate flights from SFO - ATL.
I'm so stingy with my miles

!
Truth be known, they'll probably enjoy the time apart

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I finalized the transaction back in November. Delta's CSA's were friendly and patient while we worked out a schedule. The one drawback - me wanting to get them onto the same flight. No sweet talkin' or Metal Flashing made any difference. Status and verbal linguistics matter not. Once you book it, it's set in stone!