Seconded. The other lines keep their prices artificialy high in order not to undercut the debt ridden tunnel. If the Tunnel went bust and then reappeared as a debt free concern, the ferries couldn't compete. The Monopolies Commision apparently hasn't noticed the price fixing.
Your best bet for Fally is Harwich-Hamburg (the link to Bremerhaven ended in about 1985). The ferry drops you off at the LandungsbrÃ¼cken and it's fairly straightforward to get to the autobahn from there. A good tip is NOT to go through the Elbtunnel, it's absolute murder and chokka at most times of the day. Instead, turn right onto Willy-Brandt-Strasse (it might still be named Budapester Strasse on older maps) and head for the bridge over the Elbe (ElbbrÃ¼cke). It's also the start of the autobahn.
PS. Every ferry that goes up the Elbe to Hamburg is fined for speeding. They're supposed to keep below a certain speed to avoid large waves from the bow which hit the shores on both sides and undercut the dikes. But the saving on turnaround time more than makes up for the fine, so they just give it some welly.
Ferries to Hamburg stopped years ago. They (DFDS) moved the crossing to Cuxhaven then eventually stopped that one as well. The nearest ferry port from UK for Fally is Rotterdam. About 4 and a half to five hours driving time. You could try going to Esbjerg in Denmark, but it takes just as long to drive down and the crossing time is well long.
Regularly drive trucks to Germany we always use Norfolk line Dover to Dunkirk they run every 2hrs. One word of warning ignore the sat nav as you come off at Dunkirk and follow the signs to the motorway as the roads don't match the sat nav.