This pre-release is reviewed in Serbian computer magazine "Računari" ("Computers") in it's December 1991 edition, although it was most likely shipped to testers in June 1991.
According to the article, this pre-release version is officially labeled "Beta Release 1" (which confirms the assumption that build 34e is nearing Beta 1 stage) and was shipped on five 3.5"-1.44MB floppy disks. The rest of the article compares it to Microsoft Windows 3.0, listing all of the improvements over it which would later be seen when Microsoft Windows 3.1 finally shipped.
As of this point, support for Real Mode (640 KB) was removed, which may also explain the use of fewer disks (five disks as opposed to six), and also the fact that Real Mode was already highly crippled as of the preceding version that was shipped to testers.
