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It has long been a primary objective of cosmology to understand the apparent isotropy in our universe and to provide a mathematical formulation for its evolution. A promising school of thought for its explanation is quiescent cosmology [Barrow] which already possesses a mathematical framework, namely the definition of an isotropic singularity [Goode], but only for the initial state of the universe. A complementary framework is therefore necessary to also describe possible final states of the universe. In 2009 Hohn and Scott [Hohn2009] introduced new definitions of an anisotropic future endless universe and an anisotropic future singularity, whose structure and properties differ significantly from those of the isotropic singularity, offering a promising realisation for this framework. The combination of the three definitions together then provides the first complete formalisation of the quiescent cosmology concept [Hohn2008]. All three definitions involve a conformal structure associated with the initial or final states of the universe. In the 2009 paper, for the sake of completeness, Hohn and Scott also introduced new definitions of a future isotropic universe (FIU) and an isotropic future singularity (IFS) representing isotropic end states for the universe. Recently there has been considerable interest in a new class of cosmological events, including Big Rips, Sudden Singularities and Extremality Events. Specific definitions of these cosmological events have been provided by Cattoen and Visser [Cattoen] for FRW cosmologies with scale factors of the form of a generalised Puiseux series expansion around the time when the cosmological event occurs. Here we investigate the same class of FRW cosmologies to determine when they admit an isotropic past or future singularity or represent a past or future isotropic universe. A correspondence between the conformal structure of these past and future end states for the universe and the definitions of cosmological events provided be Cattoen and Visser can then be provided for this class. Additionally, for general FRW cosmologies, we establish the precise conditions which the scale factor must satisfy in order that the cosmology admits an isotropic past or future singularity or represents a past or future isotropic universe. J.D. Barrow, Nature 272, 211-215 (1978) S.W. Goode and J. Wainwright, Class. Quantum Grav. 2, 99-115 (1985) P.A. Hohn and S.M. Scott, Class. Quantum Grav. 26, 035019 (2009) P.A. Hohn and S.M. Scott, Int. J. Mod. Phys. D 17, 571-576 (2008) C. Cattoen and M. Visser, Class. Quantum Grav. 22, 4913-4930 (2005)

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