Yes the Game Instance exists the whole game lifetime. Yet when you call it (Get Game Instance) you should be casting to your specific GI class.
To save on the cast cost you’d save the cast result to a variable. Then use the variable reference.
When you “use” the reference you should be checking if the reference is valid (not empty/null). Especially if you get it from another class.
e.g. You create the reference in the controller and then use it in another class …say pawn.
Get Controller → MyGame Instance (is Valid): [TRUE] → do something with it.
Per node info in docs: Setting an existing timer will reset that timer with updated parameters.
Timer Handle is updated every time you call the timer.