Update 15. November:
Today, construction works are getting into a second stage, and this will affect long distance railway service. Detailed information about DB time table changes here (German). For metronom information look here (German). Passengers will have to use S-Bahn or the remaining long-distance trains from Hamburg-Harburg or Altona to reach Hauptbahnhof. S-Bahn traffic to and from Hamburg-Harburg will be expanded.
2. November 2013, Deutsche Bahn is starting track construction works: 22 railway switches will be renewed in the southern part of the main railway station in Hamburg. Works will continue throughout November until 2. December.
Big construction machinery will be used, and this will affect railway services of regional and long distance connections.
“Metronom” trains will not be able to serve Hauptbahnhof on several days and will be redirected, stopping in Hamburg-Harburg or Hamburg-Bergedorf.
Passengers will have to use S-Bahn or the remaining long-distance trains from Hamburg-Harburg or Altona to reach Hauptbahnhof.
S-Bahn traffic to and from Hamburg-Harburg will be expanded –
– Many trains from Hamburg to Itzehoe, Kiel and Flensburg and vice versa are starting and ending in Hamburg-Altona. Please use S-Bahn to from and to Altona to Hauptbahnhof
– trains from and to Lübeck are running regularly
– timetable changes are included in the electronic media and apps
– please refer to “metronom” timetable changes on metronom website (in German)
– detailed information about Bahn timetables online (in German)
Source: DBahn press release (German)