V1.0: Find last instance of the weekday in each month. You choose which day of week and which year press "Go" and it will list the last date of the day in each month of the chosen year.

This is just an example that you can use in another solution.

V1.1: In this version we add a feature that will allow us to choose a date and find out if in UK it is winter or summer time. In the UK the clocks go forward 1 hour at 1am on the last Sunday in March, and back 1 hour at 2am on the last Sunday in October. The period when the clocks are 1 hour ahead is called British Summer Time (BST). There’s more daylight in the evenings and less in the mornings (sometimes called Daylight Saving Time). When the clocks go back, the UK is on Greenwich Mean Time (GMT).