I'm still too confused

about cuddling, that's why I usually use Milk, but I decided to stop using Milk at least for a while, so I need some info if anyone can help please.
They say I should cuddle the kitty 30 mins per day, but what's the "day" for the kitty? when does it start and end?
For example If I cuddle my kitty at 8 pm on a day, any cuddling before 8 pm next day is pointless?
And what if the kitty fell asleep in my arms, would cuddling affect it? it happened to me today that's why I ask

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I need to know when the cuddling works and when it doesn't work please.