You should be able to update your 2017 USB with the new 2018 files and continue to run it from the external drive.
_________________________
John

HP Win10Pro-64, 8GB
ASUS Win10Pro-64, 16GB
HP Win7Pro-64, 8GB

H/W-Behringer U-Phoria UMC404HD, Casio Kbds
S/W-BB/RB2018/Sonar/Reaper/Studio One/Samplitude/MixBus/Notion/Finale/Noteworthy/NI Komplete/Halion/Garritan/IK
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