Originally Posted by
MichielR
If coming from a secure, non-Schengen country, the train between T2 and T2S has a non-Schengen part for that scenario.
Not only does the train have Schengen and non-Schengen sections, it also has separate clean non-Schengen and unclean non-Schengen sections. ^
So passengers arriving from clean non-Schengen countries can transfer to other flights while remaining 'clean'.