I really doubt they'd make us start over 100% again. What might happen is us essentially importing our saves over in the sense that we'd have our Character data migrated, but we'd still have to lose something. My best guess is they'll do what most games do. Make us 'Start Over' meaning that we'll have our Levels + Light Level intact for 2.0 but we'll 'lose our power'. We'll probably be given Base Gear that keeps us at 400 light but isn't our current Eq's from 1.0. They'll make us get gear specifically from 2.0 only because the old gear from 1.0 won't have the same setup or configuration as 2.0, depending on what improvements or changes are made to the weapon and armor systems. Who knows if Light will even still be a thing? Also, in terms of progression, they might also 'reset' our sub-classes too, unless they literally re-use all of the sub-classes from 1.0. This would kind of limit them in terms of introducing new sub-classes, because we'd all be max in the first 3. At the end of the day though, this is just a guess. In a perfect world, they won't make us completely restart, but I can believe that they'd strip us of our Iron Lord power from RoI and make us a normal Guardian again. Which probably means that everyone will start at Level 40 with 400 Light but that will be the starting levels for 2.0. meaning we're all weak again.