Here are the posters amended based on the feedback of Joe. He said that the dates weren't working where they were or in bold along with the titles. He also suggested that the columns of type were too close together and interfering with one another.
Here is my ammendmets: I spaced the text apart by another singular column and 4mm gutter, allowing each column of text to breathe on their own. I also moved the time to below the dates and put them in Gill-regular rather than bold so they drop down in the hierarchy and don't compete so much.
I've also reduced them in scale from 762x1016mm to 356x559mm. This means it will now fit on an A2 sheet of paper, making it easier for me to print off example posters within a drop-in period because the digital print room is so heavily booked right now.