We aim to continue our investigation of the high temperature magnetic interactions in LaCoO3. Our previous experiment has confirmed magnetic susceptibility data, with a change in the internal field distribution being observed at 510K. We conclude that the muons are sensitive to the short range ferromagnetic interactions between some Co3+ ions, most probably in high susceptibility regions probed by our transverse field measurements. However, the nature of the Co3+ ion's spin state in this high temperature region was not fully explained by our data. We therefore propose to continue our experiments with further zero field and longitudinal field spectra, taken between 400K and 700K, to establish whether an intermediate to high spin state transition occurs in LaCoO3 at around 510K. The results of this work will help to resolve the controversy of the spin state transition observed at 100K.