This is solved sorting by timestamp first then by random PK UUID. Don't think a little simpler batch queries justify leaking time and quantity information or complexity of handling two types of IDs.
You wouldn't expose the numeric IDs publically, and ideally you'd use your database's automatic ID selection to avoid any complexity.
The UUID sorting works in the common case, but if you happen to end your batch near the current time, you still run the risk of losing a few records if the insert frequency is sufficiently high. Admittedly this is only a problem when you are batching through all the way to current insertions.
The UUID sorting works in the common case, but if you happen to end your batch near the current time, you still run the risk of losing a few records if the insert frequency is sufficiently high. Admittedly this is only a problem when you are batching through all the way to current insertions.