I don't like when an application is too verbose about what it is doing during the interaction, it usually is a red flag about usability. Then toasts notifications opens a lot UX issue (how to stack them, auto-close o explicit button, etc).

Maybe the row could simply change is aspect and present the "sent to top" info.

Anyway, as you mentioned later, users should quickly learn how it works, and after a while they will no longer pay much attention to these details.