How upgrade from LR5.7 to LR 6?
Download and install the trial from the Adobe webpage. It will install as LR CC 2015 trial (30 days).
If you decide for a CC subscription it will automatically be activated once your AdobeID is updated with your subscription.
If you decide you want to license as stand-alone (perpetual) buy the upgrade from here, scroll down to LR, hit Buy and select the upgrade option.
Use this guide to activate the license.
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