Monday Hour One query

Hi, just watched the Monday Hour One videos and they were so helpful. I can see the use and purpose of it immediately – I waste so much time, procrastinating and leaving things until the weekend. However, one query. In my job, (a journalist), my editor will ring up and say “we want you to do this for tomorrow” – I just can’t schedule that on my calendar on a Monday. – it may happen, it may not. When the coaches said don’t change your calendar unless it’s a real emergency – like, “there’s blood involved – this doesn’t fit for many jobs. How do you work this out? I have a book to write and many things that are my priorities, but I need to be in someway flexible too. How do you do this, realistically? Many thanks.