Tomorrow I will pick up new 2017 MacBook Pro (1TB SSD/16gb ram) at local Apple Store. Will ask their techs to transfer 100% of everything from my Oct/ 2012 MacBook Air(512 SSD, 8gb ram) to the new MacBook Pro(2017). Presumably I will leave it overnight and they will simply connect computers via Thunderbolt for fastest transfer. How may I be assured that, indeed, 100%/everything will be transferred? What should I do at home before taking MBAir to store? I have my MBAir backed up on an external hard drive as well. Need advice today if possible. Sorry for the late notice. Thanks in advance to all who can help!