Please, set up a review communication channel for those affected players to use if AFTER all is done with your steps, Beta, Telemetry, Restore Date, our judgement yields things have been missed. I can't imagine with all the Quests, Comp, Achievements, Items, Bank presets, Slayer Codex, Drop Logs, etc. etc. ... you will have things perfect. If I'm wrong.. then I praise your competency, but... don't be that company that limits the fix cause the number of players won't count. (business decision)
We will definitely have some clear support paths for everyone after Full Restore day. With anything involving this much data, there's always a potential for outlier issues - and we'll be ready to support from Full Restore Day onwards.