Underworld Release Dates

I'm trying to find the proper original release dates for Ultima
Underworld, and Ultima Underworld II, (as well as the playable demo
for UU1).

Searching usenet posts through Google Groups, the first reference to
the Ultima Underworld Demo was March 13th, 1992 --- but people were
playing the full game about a week or so later, so the demo must have
come out quite a bit before the store release I'm pretty certain.

I know that a stolen warez release predated the store release for both
games, but people reported buying a copy from a store around March
27th, 1992.

Now, what's odd is that gaming sites have a bunch of different release
dates -- stranger still is that a good number of them put the release
date of UU2 BEFORE UU1.

I see a date flying around of June 1st, 1991, but based on usenet
posts this must be incorrect.

I know for a fact that UU1 came out well before Wolfenstein 3D
(release date of May 5th, 1992).

It seems to me that the real dates are around:
DEMO: (before march 1992)
UU1: (near the end of March 1992)
UU2: (early January 1993)

Does anyone have any official info?