As posters on this thread have demonstrated numerous times, phone calls to Chase CSRs produce conflicting and incorrect answers about BA benefits.
You would have better luck calling BA, instead of Chase. After all, it is BA that awards the voucher, not Chase. Chase merely reports to BA the dollars spent.
If you call a CSR at either Chase or BA, they will simply read the Terms & Conditions to you, or give you their interpretation.
But all of these questions are clearly answered in the Terms & Conditions, which you can easily read yourself:
www.ba.com/redeemfor1travelfor2
.