The ‘issue’ that plagued him was natal Mars square to all the Taurus planets bar Mercury, and inconjunct Moon. He felt to have been enchained by circumstances, caused by the one mistake made in youth that dictated and was paid for with his life. It took the Uranus opposition to bring about the circumstances necessary to change the second half of it!
The chart owner may have experienced something similar when younger. The first Saturn return had occured, but with natal Saturn in 12th house conjunct Sun, ‘restrictions’ of one kind or another may not have brought the safety and security that a Taurus Moon also longs for , but given a suffocating effect to which the non-personal planets may have added their influence leading up to/ at/ until ‘the given point in time’ indicated.
Much depends upon the significance of Saturn’s meaning. Knowing nothing of the individual’s life, the mind can relate to a withdrawn life from public, life Imprisonment (Sun), cultural/ higher education issues (ruler 9th house?), a life-long chronic debilitating disorder and/or a crisis in faith (135*Neptune), general health (Jupiter), and/or the legalities concerning 9th house events.
Tr.Mercury is separating from the trine to Sun-Venus. Pleasant news?
Tr. Mars-Sun trine Saturn. Mars in a stained aspect to its natal position could act as the trigger towards forthcoming events, involving the 4th and 9th houses.
With only transit Uranus in the 5th house in a tense aspect to natal Saturn, yet trine Mars (ruler 12th and 7th house), a sudden social, (un)willing change in a situation would be affecting the person. Marriage, partnership, release of some kind?
Although Tr. Neptune and Pluto both form positive aspects to natal Pluto, their significance might be more on a global rather than personal level, of which the chart owner is then an inclusion in statistics of the time.
A secondary progressed/ S.A.D chart over the same period would provide any ‘life-changing’ situation and/or direction, for which the transits provide the urges towards them.