1 - Look quickly at ascension Level under hero icon in top left on Main screen Note the value
2 - Get to a new level
3 - Look at the level on the Splash Screen
4 -  Look quickly at ascension Level under hero icon in top left on Main screen - it is the same as the splash screen and the number you wrote down in step 1
5 - Do something ( change heros, move, open a chest) There is a delay for the main screen to update
6 - Look at the ascension Level under hero icon in top left on Main screen - It is now one higher (the new level)