I would also guess kind regards, but in 50 years of speaking and writing formal/informal/technical English I've never seen that one!
I notice in Skype groups that I've been involved with, I continuously see things such as-
u = you
wt = what
hand = have a nice day (I thought it was a body part, my mistake!)
k = okay
ruf = rough ( because the correct spelling is too hard and makes no sense, or so I was told)
thot = thought (not to be confused with the Norse God Thor)
picter = picture
and the list goes on! (Note: the last 3 aren't accidental mis-spellings. I was told directly this is a better way to spell these words because English spelling makes no sense and is too hard to remember).
I have had times where I had to ask people what they were trying to communicate and they are shocked that I don't know what they are trying to say.
It's a different world my friends, laziness is king! :)