Is it possible to automatically send a proof reminder?

Yes, that is possible.

Having this ability means that there would be no need for a CSR/Salesperson to manually track, and potentially fail to follow up on any particular proof, resulting in fewer missed deadlines and less time spent on low value tasks such as sending reminder emails manually.

tFlow provides a function that allows to send a reminder email if a proof does not get approved after a set amount of time has elapsed.

In the case the proof has had no action taken after a defined number of days then a reminder is automatically sent.

The function can be enabled in the system settings:

In the settings it is possible to define the number of days afterward the reminder notification will be sent.
It is possible to also includes the internal users to the list of the recipients.