Yeah there is an added delay (2/5 seconds depending on whether it will kill you) when on unfinished level end and you have a potion that could somehow affect the situation. Kept the timing fairly short so that you'd still kinda need to be aware of what you could do to pull it off. Some kind of indication might not be a bad idea as it still would realistically need to be known first hand even with it.
By the way, there are also undocumented hotkeys now added to potions (number keys) to help with pull off these "grace period" quaffs or even healing mid thundering.
Aight, will keep an ear out more critically on the pylon sounds. Have to admit, I didn't really listen to them enough...