It's still present even in the latest EC20E firmware EC20EQAR02A09E2G from 2016-09-24:
ynezz@ntbk:/opt/devel/flexisbc/quectel_ec20/EC20EQAR02A09E2G$ grep QLINUXCMD
Binary file 9615-cdp-recovery-image-9615-cdp.yaffs2 matches
Binary file dsp2.mbn matches
Binary file 9615-cdp-usr-image.usrfs.yaffs2 matches