Erratum: Cloud Atlas: High-contrast time-resolved observations of planetary-mass companions (The Astronomical Journal (2019) 157 (128) DOI: 10.3847/1538-3881/ab037f)

In the third paragraph of Section 5.1, the calculated rotational breakup limit for AB Pic B omitted a factor of 2π. The rotational breakup limit of AB Pic B should correspond to a 1.57 hr rotation period instead of 0.25 hr. Therefore, the observed 2.1 hr periodic signal in AB Pic Bs light curve should be equivalent to 75% instead of 12% of the breakup limit. With a 2.1 hr rotation period and for angular momentum-conserved contraction, the rotation velocity of AB Pic B will likely approach or even exceed the breakup limit when AB Pic Bs radius approaches 1 RJup.These corrections do not affect any conclusions of the original paper.