Well I've tried to do that multiple times but it simply won't turn back on. After it was installed I began to get notices that I needed to turn on Windows Defender. The Windows 10 Professional upgrade (32-bit) went smoothly and everything worked afterward (including Windows Defender) so I used the Spybot 'Post-Win10 Spybot-install' icon which had been placed on the desktop to reinstall the new 2.5 version of the program.
Knowing that the Windows 10 install program would remove Spybot S&D 2.4, I went ahead and uninstalled it myself before the upgrade.
