Boots, the producer whose work on Beyoncé’s surprise album made him an instant star last winter, had been talking about working with El for a long time before he contributed ominous magnificent sonic swirl to “Early.” “Boots and I had been friends for a couple years,” El recalls. “Before he did the Beyoncé thing, him and me were talking about doing some music together. I went on tour, and when I came back he was Beyoncé’s producer. So it was pretty incredible. But yeah, we had never really stayed out of touch.”