Randomly Creates New DB Table

Why does Save CF7 sometimes create a new table on it’s own? Is there any way to prevent this?

I’ve used Save CF7 for about a year now. About six months after I began using it, Save CF7 created a new database table all on its own, no action on my part.
For example:
The original database table was:
SaveContactForm7_1

The new table:
SaveContactForm7_5

I discovered this because I use the table name to fire a custom php script that emails a csv, and then truncates the table at 11:59pm. So if the tablename is occasionally changing all by itself, this script is deactivated.

I began using Save CF7 on a second site 5 months ago, and today I noticed that Save CF7 created a new database again.
Original table:
SaveContactForm7_1

The new table:
SaveContactForm7_3

Why does Save CF7 sometimes create a new table on it’s own? Is there any way to prevent this? Does it have something to do with software updates?