In June of 2018 I saw Venus with the naked eye at about 16:00 UTC when the Sun was at an altitude of 30 degrees. To do this I used my GOTO telescope as a guide as to where to look. The sky was particularly clear and a deep blue which suggests not much of the usual milky haze we get in the UK. Even so spotting it wasn’t easy if I looked only a degree or so off target then finding it again was tricky.
I’ve never seen Jupiter with the Sun in the sky.
By the way I grew up in Rugby and have many happy memories of observing there. Attached picture is Venus (barely visible!) from Rugby in 1983.