6678700 : Rel 11i to 12.1.1 Upgrade : BOM / CST Worker 'cstmtaupg.sql' fails with 'ORA-06508: PL/SQL

@/usr9/apps/apps/apps_st/appl/bom/12

Hi there
While applying the 11.5.10.2 to 12.1.1 Upgrade (Patch #6678700), the Costing worker task 'cstmtaupg.sql' fails as follows :

   sqlplus -s APPS/***** @/usr9/apps/apps/apps_st/appl/bom/12.0.0/patch/115/sql/cstmtaupg.sql &un_inv &batchsize 8 16
   declare
   *
   ERROR at line 1:
   ORA-04063: package body "APPS.CST_SLA_UPDATE_PKG" has errors
   ORA-06508: PL/SQL: could not find program unit being called:
   "APPS.CST_SLA_UPDATE_PKG"
   ORA-06512: at line 15

We can see that it's the Package Body which is not being found :

   SELECT owner,object_type,status
   FROM dba_objects
   WHERE object_name = 'CST_SLA_UPDATE_PKG' ;

   OWNER                          OBJECT_TYPE      STATUS
   ---------------------------- ---------------------- -------