Of course it could also be because he correlates environment cues to bed time.
Either way, birds are smarter than you think until you spend time observing them.
> birds are smarter than you think until you spend time observing them
People, too.[1] https://www.mlive.com/news/2020/09/zoo-separates-foul-mouthe...
He used to say his name sort of (if you added some human pattern recognition magic) but stopped after we moved apartments. No idea why.
The worst is when he mimics human speech patterns. You can tell it isn’t words but it’s close enough to distract you every time.
Main thing with parrots is that they’re more work than people think. Like human children they get bored, have tantrums, internal emotional states, and respond to the same stimuli differently based on mood. And unlike children they cannot be reasoned with. Some are smart enough to lie and obscure because they have theory of mind.
And they stay like that for 30 years. Some species even longer.
The conclusion is that the birds interpret the sequence ABC - D as a meaningful unit, different from its constituent parts, which is a kind of interpretation only previously confirmed in humans.