My S5 screen comes on when I receive a text--but before I actually get the text

[AC Question]

My S5's screen normally turns on/lights up when I get a text. This is normal and expected. However, recently, it turns on prior to the actual text arriving. What I mean is that normally, I'd receive the text at the same time as my phone screen turning on, so I could see the shortened version on my lock screen. Now, by the time the text actually comes through, the screen has already turned on and off. It's like a heads-up now, rather than a way for me to see who sent the text and the first few words.

It's so strange and I'm not sure what has happened to cause it other than an update to the system.

Any thoughts?