There will be at least one more DvD sequel (this is official information), but I'm not sure whether or not there will be another one after that. Perhaps the 13th DvD is going to give a little more background information to provide the stage for the TV series (but this is just a guess).
Personally I don't think the TV series needs to be the end of of the DvDs. Not all stories can be told in little more than 20 minutes. Moreover the quality of the animation in the series, though not bad, is definitely worse than the quality in the DvD series. There are instances in which the character's faces look positively distorted.
I don't see why the DvD series would have to be stopped just because of the the TV series. The statement I made about the continuing of LBT in general applies to the DvD series as well. So long they have good stories left to be told, why on earth should fans whish for them to stop telling them?
