The entry refers to the anti- (or E-) conformer, which is by far the lowest one. Millimeter and submillimeter transition frequencies were reported by
(1) L. Marguleès, Z. T. P. Fried, R. A. Motiyenko, B. A. McGuire, M. Sanz-Novo, V. M. Rivilla, I. Jiménez-Serra, and J.-C. Guillemin, 2026, J. Phys. Chem. A 130, 2893.
The entry should be sufficiently accurate for observational purposes. Transition frequencies with calculated uncertainties exceeding 100 kHz should be viewed with caution. The dipole moment components are from a quantum chemical calculation in (1). Please note that the weak b-type transitions are still quite uncertain.