Send a Mid-Autumn Festival blessing message to the leader in advance? What are we going to do? Will it be bad? They didn't reply to any text messages.

Don't worry, under normal circumstances, the leader won't care, first, because he will receive many such messages, and second, because it is a blessing message after all, a small mistake will not change the connotation of the message, but an apology will be a bit disappointing. One day in advance may actually impress another leader. If you really want to make up for it, send a different (better content) short message on the Mid-Autumn Festival, but I believe it will also be submerged in the short message wave.