I tried to find some material but didn't have the time left for a very extensive check trough my pile of information (auction season
)
I did however find some material which might be interesting, the wavy decoration seems to make its way slowly to the nort west regions of Germany. Only a assumption of course, to little facts to support this claim.. but still.
Link to bonhams auction of 27th november item number 182.
http://www.bonhams.com/auctions/20803/lot/182/
Other interesting items where sold in this auction as well.
Christies might have a good database as well on this subject?