the good news is that this Brainteaser is about PORT wine!
Of course there will be some of you whom will be forced, when faced with your ethical dilemma, to go straight to Google and torture yourself for a few hours or daze.
I considered a prize, like paying the way for the winner to attend the 1896 dinner, but there is no way for me to know who will be honest and do this without spending the weekend on Google to obtain the answer OR contacting ANY Port producer.
So the prize for this one will be ... the first FTLOP T-shirt and hat to come off the production line ... shipped anywhere in the world by yours truly ... or hand delivered in Portugal or London later this year at the Dow 1896 dinner.
In order to win, an individual must get part A + B correctly. One without the other makes your answers invalid. Ready?
A. Name ALL of the Port Shippers who have ever produced Garrafeira Ports.
I'll give you TWO hints on this: Niepoort

The second hint is: There is more than one other Port producer.
B. Between which specific range of years were these Garrafeiras produced (NOT including Niepoort's? (example a range like 2010-2086, is what I am looking for)
I'll give you TWO hints on this too: This did not occur in the 21st century

The second hint is: They were not produced during the 18th century.
Come up with the answer before 9 a.m. London time (GMT?) on Monday and I'll toss in a 1955 Sandeman or Graham's VP from my cellar. If you speak to a Port producer or use Google, I may not find out ... but you'll still be disqualified. JK.
Let the games begin!