In addition to the AAdvantage® miles earned with your CitiBusiness® / AAdvantage® credit card, eligible businesses can earn points towards round-trip flights, Admirals Club® access, AAdvantage® elite status and more with Business Extra. Through May 31, 2021, join for free with code 21CITI650 to receive 650 bonus points when you complete an eligible flight within 90 days of enrolling — that’s enough for a one-segment upgrade.
Emphasis mine.
Just got this mailer from Citi about a new member bonus offer for joining Business Extra if anyone is interested. Details below:
https://www.businessextra.com/i18n/c.../21CITI650.jsp