"Come in between March 9 – 11 and purchase your favorite drink or bite to eat, and we'll load a coupon for a free breakfast sandwich to your account within 24 hours.*
Your free breakfast sandwich coupon will be valid for 7 days after it's loaded to your account. Check the pay tab in the app, or ask your barista to use it."
I don't know if this is targeted (Rewards customers) but in my starbucks app I see an offer when clicking the "pay" option, YMMV ...
Code 2257 - Enjoy a free breakfast sandwich
Expires March 19th | Code 2257
In my online account I see:
March 10th Offer Received
Code 2257-Enjoy a free breakfast sandwich
This code has been used in the past before: old 2016 post
Seems like all you have to do is tell the barista the code when ordering.
Other sites mentioning the same deal:
I'm not affiliated with any of the sites mentioned in this post.