Envelope III - "Shuffle"

As I posted earlier, I have indeed received a third envelope. Since the outside is the same as the second one, I don't think there's any point in wasting everyone's time and bandwidth showing pictures. So, here we go...

Front

"Shuffle". Do note, also, that the bottom-right corner has been cut off; I'm not sure why. In any case, I think the purpose of this may be something due to the differing layout of this paper from the others. No named god, no crappy poetry...

Reverse

"Madness is catching. Don't get caught".

Good advice, for sure. The symbol's in the corner, if you can't quite make it out.

Inside

I took three photos because I'm crazy like that. Plus, it might be hard to make stuff out on the single shot. Anyway, here's what's on there. I've written it out in approximation, obviously, not exactly as it's laid out. Use the original pics as reference.

vitamors.blogspot.com

28/09/20?

(Unimportant.)

Do not trust friends.

Trust (symbol).

06/
07/
83?
(Unimportant.)

c4 c5

Qa4 Qa5

Qc6 Qc3

Qxc8# 

Sorrow.

0200

1900

20/08/66

(Unimportant.)

That was annoyingly long. Anyway; the first line is the URL of this blog, which obviously means my little friend is aware of the blog. Perhaps interestingly, it's where the sender's address would be if this actually was a letter - I took the wisest precaution and changed my computer password. It's probably a bluff, but t'is best to err on the side of caution, especially if this person knows I'm analysing the envelopes.

A quick google of 28/09/20 gave no results that seemed interesting. The next line say that I should not trust friends, but I should trust random symbols... yeah, I'll get right onto that. A google search for what I'm guessing is a date yielded nothing interesting but this: Polish military sights a UFO. Related? I have no idea.

It then gives a bunch of random letters and symbols, then "sorrow". I don't know what to do about that. It then says "0200 1900"; times, possibly? I also googled 20/08/66, finding nothing interesting there.

The obvious question here is: what do the dates mean? I have no clue. They have no significance to me, to my knowledge... hm. If anyone knows anything about those dates, tell me. Given the day/month/year set-up, keep in mind these are British dates, not American ones (which are, I think, month/day/year? Something like that).