It is definitely allowed, but the key is that AliExpress backend does not have this function. You can try with the help of a third-party tool, Wangxiaowang erp, which is quite famous in the cross-border e-commerce erp industry. If there is a temporary interruption during the group message, you can skip the messages that have been sent on the same day, which is more user-friendly. At the same time, you can also send emails, text messages, and internal messages. Send them as you like, and don't cause harassment to buyers.