Humans are diurnal. We have chemical signals the control our waking and sleeping cycles, we are evolved with good day and color vision, poor night vision and smell, and an excellent ability to shed heat in the mid-day sun.
That being said, there exists a group of humans in a rainforest environment where the best time to be awake is twilight. For these people, the primary food source varies by wet and dry season, but either way it is fish. The old fisherman's adage is that the fish are most active at dawn and dusk. In the dry season, these people use twilight to fish in oxbow ponds and shallows on the edges of the great rivers of the forest. In the wet season, the rivers flood their banks and become long lakes. The people fish just before daybreak and after sunset, attracting small schooling fish by lantern-light.
There are other agricultural activities, which primarily revolve around gathering fruits and nuts from semi-wild orchards planted in the forest, and growing vegetables in floating farms (detailed in the linked question).
Overall, would it be beneficial for these people to adopt a fully crepuscular lifestyle? A crepuscular chronotype would be one where there are two periods of sleep per day, one during mid-day and the other mid-night. There would be two ~six hour periods of activity around dawn and dusk, with two ~six hour periods of rest in between.
Are there chemical or biological reasons why this would not work? Does the advantage of being awake when your primary food source is available overcome the poor nighttime senses for an agricultural society?
As this is a tropical rainforest, day length does not vary over the year, so no need to worry about long days or nights.
Technology level is Bronze Age. The crepuscular lifestyle would have developed after these people became primary fishermen, perhaps a few thousand years before.
The humans are biologically identical to us. The environment is comparable to what one might find in the Amazon or Congo basin.