Is there a 64-bit version of Scrivener available for Windows 10?

Although there is no such choice between 32-bit and 64-bit, after adding the license key, when I checked I found that my software was 32 bit. Is there any way I can get a 64 bit version for my PC. (Windows 10)
Also - would I lose any preexisting Scrivener projects in the shift (if it is indeed possible) ?

Version 3, currently at Release Candidate 8, is available in 64-bit; version 1.9 not.