Oracle 11g Recovery – Resolving ORA-01190 Control File Error

I am running Oracle 11GR2, Enterprise Edition Release 11.2.0.3.0. I got one of my Test DBs corrupted today. Luckily, I have 2 weeks of backups in the Net Backup server, so I thought, "This is easy, I just restore from the latest backup and I should be good in about 2 hours!"

But I kept getting this Oracle ORA-01190 error. So I changed my restore time about 30 minutes earlier, than I got the same error.

  SQL> alter database open;
alter database open
*
ERROR at line 1:
ORA-01190: control file or data file 1 is from before the last RESETLOGS
ORA-01110: data file 1: '+DATA/t1/datafile/system_01.dbf'

After I made the restore time changes, I got this error:

SQL> alter database open resetlogs;
alter database open resetlogs
*
ERROR at line 1:
ORA-01152: file 1 was not restored from a sufficiently old backup
ORA-01110: data file 1: '+DATA/t1/datafile/system_01.dbf'

This is my rman restore scrpt

run
 {
 allocate channel D1 type sbt_tape parms='ENV=(NB_ORA_CLIENT=t2.abc.com,NB_ORA_COPY_NUMBER=3)';
 allocate channel D2 type sbt_tape parms='ENV=(NB_ORA_CLIENT=t2.abc.com,NB_ORA_COPY_NUMBER=3)';
 allocate channel D3 type sbt_tape parms='ENV=(NB_ORA_CLIENT=t2.abc.com,NB_ORA_COPY_NUMBER=3)';
 allocate channel D4 type sbt_tape parms='ENV=(NB_ORA_CLIENT=t2.abc.com,NB_ORA_COPY_NUMBER=3)';
 set until time "to_date('16-MAR-2016 15:20:00','DD-MON-YYYY HH24:MI:SS')";
 restore controlfile;
 restore database;
 alter database mount;
 recover database;
 alter database open resetlogs;
 }

Shall I start to use SCN method to restore my database? Is there a clear indicator for me to see the time I can surely restore my database from its backup files?

Thank you so much!