My boys & girl have a routine of their own.
In summer it's when it's dinner time, they may choose to come out after or occasionally prefer to go straight to sleep. Dinner will be about 7pm. Bed between then & 9pm. Winter they start to scream for dinner about 4pm & settle themselves
to bed shortly after. They rise about 8am summer winter. They don't make a sound until they hear us up, then you can hear them talking quietly
My cockatiel will scream bl**dy murder when it starts to get dark, he wants bed & he wants it NOW!!
He sleeps with his favourite toy with a bell on it. If he gets disturbed he viciously attacks the bell to let
us know that he's pee'd about being disturbed LOL
My sunnie screams bl**dy murder once 'dinner' is mentioned, yep, they ALL know the word dinner! Once she's been fed she snuggles in to sleep, on longer days she will come back out for a play & then back to bed. She sits on her highest perch & leans against her favourite toy. That's how she sleeps & it looks extremely uncomfortable.
My eclectus says 'want ya dinner' when he's getting hungry. He also see's my cockatiel as his 'big' brother & follows suit
with him. If my tiel is in bed or eating, so will my ekkie be. If my ekkie doesn't notice my tiel in his cage eating or sleeping, he's more than happy to stay up as late as he possibly can. Most of the time he will go & eat his dinner, then want to come out again for a few more hours of play & snuggles good night. When he's ready for bed he will say, 'go see Cricket?' (my cockatiel).
They all share a bedroom which has a dimmer light switch & an oil heater for winter. Because of mouse & rat problems in the area I remove the food after they've eaten, I dim the light just a little, not too bright, not too dark. Too bright & my tiel gets angry LOL About 1 or 2 hours later I dim it as far as it will go & they all get into their positions of sleeping. I give them 1/2 hour to settle before turning the light off.