I am assuredly not an astrologer, but what I can tell you is that what time is defined by what "sign" was set a long time ago. It doesn't change, even though where the Sun is on any given day does.
"Now everyone was giving her that kind of look UFOlogists get when they suddenly say, 'Hey, if you shade your eyes you can see it is just a flock of geese after all.'"
"You can't erase icing."
"I can't believe it doesn't work! I found it on the internet, man!"