installer trying to read wrong USB device while boot?

[Yukimi Conary]

Hello all.

 Today I tried fresh install again with /
 "DragonFly-x86_64-20170612-DEV-v4.9.0.309.g2032f7.img"
 But boot will abort because missing boot device.

 da9 = SanDisk Extreme 32GB USB (Live img)
 da8 = Toshiba SSD 64GB via USB 3.0 converter (target to install)

 Is this Installer mistake handling with da8 and da9? (see photo)

 UEFI related issue? mobo firmware bug? or...

 ofcourse it is not only once. it is reproducable.
 Dfly 4.8.0-REL made same phenomenon before this trial.

 Installation was success with typing "ufs:da9s2a".
 as a result no need help for how to installation.

 Comments are welcome.  Thanks for reading my terrible english.
 Sorry if it's duplicated. Similar reported issue was looks like closed...

 - spec -
 M/B Asrock C70M1 (recent UEFI firmware)
 VGA RADEON R5 230 1GB PCIe
 MEM 4GB
 SSD/HDD
  OS(ufs)   : 64GB SSD (target)
  DATA(hammer) : 1TBx4 (span) - same as offline/online
 ATEN CS1764A Switch
 Its Physical node. not VM guest.

ykm
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