It seem to be happening to me often. I have just started freelancing remotely. For now, I am targeting small project (1-7 days long).
Usually I try to keep a small backlog of projects so I am not completely without any work at any time.
Once I have a new project with 10 days deadline, I will began it after 3-4 days (after finishing older projects).
But I already noticed some clients want daily updates from next day. I of course wouldn't want to work with such clients again, but what for now.
What do I tell them everyday if I have not even started yet.