Some of the recent chapters were about an importance of not wasting time, and I'm not sure if that was or wasn't a hidden message.

I mean, in the story universe, Harry will not be suddenly given a huge dialog window saying: -- "Harry, now you have to make an important choice, and the fate of the world depends on it. Will you: a) trust Quirrell, b) say everything to Dumbledore and ask him for information and help, c) ask Minerva to join your heroic team and help you research meta-spells, d) do a dangerous ritual involving time turners, advanced Patronus, invisibility cloak, and partial transfiguration?"

Instead, the possible solutions will be gradually taken away from him without a warning. He will probably not even get a feedback when the last one is gone.

But of course I am mixing in-universe and out-universe here. It is still possible that the dialog window will be displayed to us, readers, at a proper moment.