Hola lunero, por lo que veo hay una versión actualizada de ADMT para W2012R2
Released a new ADMT v32 revised version that now supports Windows 2012/R2 | ItaPFEPlat
https://blogs.technet.microsoft.com/itapfeplat/2014/10/01/released-a-new-admt-v32-revised-version-that-now-supports-windows-2012r2/
E inclusive hay versiones de las guías actualizadasa Feb'2018
Download Active Directory Migration Tool version 3.2 from Official Microsoft Download Center
https://www.microsoft.com/en-us/download/details.aspx?id=56570
Download Active Directory Migration Tool (ADMT) Guide: Migrating and Restructuring Active Directory Domains from Official Microsoft Download Center
https://www.microsoft.com/en-us/download/details.aspx?id=19188
Guillermo Delprato
Buenos Aires, Argentina
El Blog de los paso a paso
MVP - MCSE - MCSA2012
MCITP: Enterprise Administrator / Server Administrator
MCTS: Active Directory/Network Configuration/Applications Configuration/Server Virtualization/Windows 7 Configuration/Windows 7 & Office 2010 Deployment/Vista Configuration
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