Pl post a link to your reference. AFAIK, there should be no issues exporting from 11gR2 and importing into 12c
How big is your database ? How much downtime can you afford ? Is there a reason for not using DBUA ?
I guess that was referring to transportable tablespace mode regarding version parameter. The database is quite small and for now downtime is not really an issue. Sorry for the misinterpretation. I was asked to use data pump to perform the upgrade. It appears things should go pretty smooth.