This article is from the British comedy FAQ, by James Kew j.kew@ic.ac.uk with numerous contributions by others.
No. The Blackadder FAQ cites this article from the Times (London), 22
October 1989:
When the fourth series comes to what its co-writer, Richard
Curtis, darkly describes as its "very definitive last episode" on
BBC1 in two weeks, it is almost certainly the last we will see of
the most slippery dynasty since -- as Captain Blackadder might
have said to Private Baldrick -- the incredibly mean Emporer Ting
covered his grandchildren in yak grease, pushed them down the
Great Wall of China and said he'd bought them a roller coaster
for Christmas...
...Curtis says: "It's possible that we'll all work together
again, but we're not likely to meet up two years from now and
decide to do something we've already done four times. There were
only four gospels, for God's sake."
 
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