Nope. If you have the Pro version, you do not need the free version. Also, if you buy the pro version after you have installed the free version, then uninstall and delete the free version.
We will send a few email reminders of upcoming renewals. If you allow your license to expire, the administration panel of the pro features only will be disabled until renewal. The plugin will function normally, and still work , but you will not be administrate the pro features until the license is renewed.