The present article presents four new linguistic features that link Early-Mandaic and Neo-Mandaic: 1. Diphthongisation and fortition of long vowels ū/ī (ࡈࡁࡅࡊࡕࡀ ṭbukta instead of ࡈࡀࡁࡅࡕࡀ ṭabuta “grace”, ࡀࡓࡁࡉࡊࡕࡉࡍࡊࡉࡀ arbiktinkia instead of ࡀࡓࡁࡉࡕࡉࡍࡊࡉࡀ arbitinkia “four of you [f.pl.]”); 2. Apheresis of y in the gentilic noun יהודיא (ࡄࡅࡃࡀࡉࡉࡀ hudaiia “Jews”); 3. Assimilation of z in the root ʾzl (ࡕࡏࡋࡅࡍ tʿlun “you [m.pl.] will go”); and 4. Internal analogy in the system of cardinal numbers (ࡕࡀࡓࡕࡀ tarta “two”). The presence of these forms in the two extreme phases of the language as opposed to their almost total absence in the canonical collections of Mandaic scriptures prove not only the ancient origin of some Neo-Mandaic peculiarities but also the wide range of varieties of Mandaic that flourished in Mesopotamia in Late Antiquity.