I do not get writer's block. If I seem to have it, it's because I really don't have a clear image of where my characters are or what they need to do. So I review my plot outline, perhaps reading over the preceding scene, and then use my imagination. There are plenty of other things to do if you have only interrupted pieces of time that day, such as updating your website or answering emails. So, don't take the day off just because writing is not working for you that day.