Perhaps I am mistaken but to me there seem to be some significant general differences between 'Hellenistic' and 'Medieaval' astrologies, although the latter derives from the former. These differences appear often but not always related to the cultural shift from Pagan to Abrahamic traditions. For example, Medieaval astrology seldom if at all still refers to the 3rd Place as 'Place of the Goddess'.
Hellenistic astrology still seems connected to underlying 'feminine' notions like Gaia and Chaos, Medieaval astrology much less if at all, generally beginning with Being or the Monad and ignoring Non-Being or the Great Vacuity.
Therefore it seems more reasonable to me not to lump the two together and that there are specialists for each, e. g. Robert Schmidt for Hellenistic, Robert Zoller for Mediaeval.