Why are strange things happening on the screen during data connection?

[AC Question]

Strange things happening on screen during data connection

I see some strange behviour while connecting to WiFi:

1) When I turn on the WIFi from the top-slider on home screen, I see "LTE" for a while near the data connection icon (as if I am connected to 4G for a while) and then it disappears.

2) When I turn off the WIFi from the top-slider on home screen, I see "LTE" for a while near the data connection icon (as if I am connected to 4G for a while) and then it disappears.

Can anyone suggest what could be the reason?