Yes.
The "ubi-initramfs-recovery-installer.itb" upgrades the bootloader, changes parittion structure to UBI based, and installs the initramfs recovery instance. And then you use that instance to sysupgrade to the specific normal sysupgrade image that you want. rc6 is currently the newest semi-release.
You should not need to ever again to use the ubi-installer. That version will remain as the recovery console, but you sysupgrade to newer builds as you want.