I executed the following command on terminal
qlaunch -r singleshot -f 2
and output was
2018-12-10 19:59:14,815 INFO reserved FW with fw_id: 15
The problem is that fw_id actually submitted (fw_id: 15) differs from that I specified (-f 2).
I think this is because args.fw_id is not specified into any function in fireworks/scripts/qlaunch_run.py. (it should be specified in 69-71th lines?)