[Ger-Poland-Volhynia] Port of departure Rotterdam

[gary and rhonda simpson]

Has anyone had experience using the Rotterdam lists available through FHC?
My grandparents Robert and Hulda Litz noted on their naturalization that
they left from Rotterdam, but their landing in Canada was on a ship from
Liverpool (SS Bavarian).
Would these lists give outbound passenger info if they only used Holland
lines for the first leg of the journey?  I understand if they used a feeder
ship that there are no records but if they were on one of the major liners
going to the US for the first part and switched ships to one going to Canada
mid journey due to cheaper fares maybe???

Any input would be appreciated.
Rhonda Simpson
Belair MB