YESDERDAY misspelling (i.e. should be yesterday)
I went in to recreate the mailing that failed yesterday so I could have another attempt in due course, and noticed the above anomaly that is the misspelling of yesterday as yesderday in the Mailing Manager.
I would also be grateful if you would let me know when you think it is going to be safe to try a second send of that mailing to the given audience.
(Actually, I have just noticed a small factual error I must research into and correct before I send it out!!)