Just signed my small business up for Business Extra, after getting a promo email that included this language:

"As an added bonus, earn 650 Business Extra points (enough for a one-way upgrade1) when you enroll by October 31, 2020 with code 20OCTand fly within 90 days."

Seems like good timing, since I'm transitioning over from Delta.

Only question I have is whether a one-way flight will satisfy. I don't see any language about it needing to be a round trip:

"This offer is available only to recipients of the email sent by American Airlines on October 9, 2020, and is valid through October 31, 2020. To earn the reward, an eligible company must enroll in the program using Referral Code "20OCT" between October 9, 2020 and October 31, 2020, and fly within 90 days of enrolling using their newly created Business Extra number. If the requirements are met, 650 Business Extra points will be deposited into the member's account within six weeks. This offer is non-transferable. Void where prohibited."