If I understand correctly, you don't need to think these two (or more?) selves as mutually exclusive. It's just that when in certain contexts, e.g., when one is setting the alarm, this self has the appropriate conditions to be the dominant one (the laziness feeling bundle is not yet present). The other self, the lazy one, is still there, but its voice is not strong enough to overpower the first.

By contrast, in the morning, the reverse is also true, only this time the lazy voice is completely empowered by the comfy environment -- the other self just not having enough power to break through through the thick wall of comfort attached feelings the body is experiencing at the moment.

To put more simply, both (or more?) are there at the same time. but one is active, the other latent.

"That's a problem for Future Homer! Man, I don't envy that guy!"

It’s really system 1 and system 2 fighting, the temporal aspect just makes the drama more striking.