Yttrium Iron Garnet (YIG) is a material with extremely wide ranging applications, having the narrowest ferromagnetic resonance linewidth of any known material. We have recently solved the magnetic hamiltonian for Yttrium iron garnet, fitting the full magnon spectrum up to 110meV across many brillouin zones, including full monte-carlo simulation of the instrumental resolution of MAPS, finding that the magnetic interactions in YIG are richer and longer range than had been previously accounted for. Following a publication which predicts unusual behaviour of the high temperature magnon spectrum (with flatter modes broadening much more than strongly dispersive ones) and the upgrade of the MAPS spectrometer, we propose to measure and reproduce the magnon spectrum of YIG at 6, 150 and 300K, using new functionality being introduced into SpinW for simulating magnon spectra at high temperatures.