I believe that upgrade path is still active, and your MCSA in SQL 2012 was automatically upgraded to MCSA SQL 2012/2014.
The MCSA: SQL 2016 certification page states"You can upgrade the MCSA: SQL Server 2012/2014 certification to the MCSA: SQL 2016 Database Development certification through a single exam"... "Take exam 762" - i.e., completing 70-762 will upgrade your MCSA 2012 to 2016.
The Born to Learn announcement of the change from MCSA in SQL 2012 to MCSA in SQL 2012/2014 states
To reflect the inclusion of SQL Server 2014 content in Exams 461-463, we are also rebranding the MCSA certification to MCSA: SQL Server 2012/2014. As changes to each individual exam are modest in size and SQL Server 2012 skills remain relevant, all current certification MCSA: SQL Server 2012 certification holders will have their transcripts updated accordingly to reflect the new credential name.