Parallel run for onroad/RPD

Hi all,
It takes hours to get one output file for onroad/RPD and ca_adj_RPD. Is there a way to do parallel runs for RPD? I tried to duplicate the .csh script with a different starting date but got the following error. I used the 12US1 domain with all NEI default inputs.
Thanks so much, and any suggestions are appreciated.

WARNING: output file already exists: MTSUP

 File "MTSUP" opened for output on unit:  90

 Processing data for:"VMT", "SPEED"
 IOAPI_DAT       :/glade/scratch/pwang/NEI_2017/INSTALL_DIR/2017gb_17j/intermed/onroad/RPD/mobl_RPD_onroad_jan_dat/VMT.ncf

 >>--->> WARNING in subroutine OPENSET
 File not available.

 ERROR: Could not open file:
 File set "IOAPI_DAT" is not currently open
 Error reading "SRCID" from file:
 File set "IOAPI_DAT" is not currently open
 ERROR: Could not read "SPEED" from file.

 *** ERROR ABORT in subroutine RDMAPPOL
 Problem reading pollutant data

Monthly_onroad_ca_adj_RPD_12US1_2017gb_17j2.csh (8.1 KB)
Monthly_onroad_ca_adj_RPD_12US1_2017gb_17j3.csh (8.1 KB)

From the info file

See Section 4B which discusses setting up DAYS_PER_RUN for your system, and also if your computer supports it you can run different months or quarters in different processing streams. For example, run January-March on one node, Apr-June on another, etc.