@Clove20 HR here - your maternity leave has to be begin when baby is born (not your due date) so if baby is 2 weeks late you’ll be able to take all 4 weeks, but if they come earlier your maternity leave will automatically start then and the period of annual leave stopped. So you might be able to carry that leave to next year, depending on your works policy, or you’ll lose it. Do speak to your manager or HR about what would work.
I’m hopefully going to take about two weeks annual leave up to my due date (which is a Friday) and then maternity will start then. I should be back at work for 3 full months in that case, but I’ll be able to work entirely from home so can go later than I would have done if I’d still been commuting.
I know first babies are more likely to be late but who knows what this one will do.
I plan to take most of the full year if not the whole year (will depend what looks sensible nearer the time) using KIT days and accrued leave to bolster the last unpaid 8-10 weeks. I hope I’ll be able to use some KIT days from earlier, I like my work and the people and will miss them. I only get SMP as I haven’t been at my job quite long enough for enhanced, but thankfully we can afford it.