When I upgrade from 188.8.131.52 to 184.108.40.206, then later to 220.127.116.11
each time I had to create a new middeleware home and base directory..
I ended up with these
18.104.22.168: /Middleware and /gc_inst
22.214.171.124: /Middleware12102 and /Middleware12102/oms (I put the base directory in the middleware folder and named it OMS)
126.96.36.199: /Middleware12103 and /Middleware12103/oms
11g to 188.8.131.52 is out of place upgrade which mean you will get a new middle-ware home. Starting 184.108.40.206 the gc_inct is outside the middle ware home.
So in 11g if you have -/u01/app/oracle/product/Middleware then i suggest you provide this during upgrade for new middleware home- /u01/app/oracle/product/12c/Middleware and inst home will be -/u01/app/oracle/product/12c/gc_inst