I know a couple of INTjs who are often late, and often cancel last minute -- not always, but sometimes. It's especially amusing because one likes to make mean comments that she "left an extra 10 minutes late" because she figured I would be late -- when she is often 20 minutes more late than me....

Flakiness isn't type related. I even know an ISTj who is sometimes an hour late to things, or is generally extremely flaky. I'm usually on time these days, as I finally learned to estimate how long things would take.

And some INTjs do guilt trip, but in a passive aggressive way...