Being able to write ‘on cue’ is critical in text-based, creative domains, since time is often a limited resource. Although numerous digital-interactive Creativity Support Tools (CSTs) are available, writing applications with features to support creative writing as a time-constrained activity have scarcely evolved since the 1960s. This is striking, since studies show that time constraints may benefit creativity. We present an exploratory survey-based, qualitative user experience study of how a writing application prototype designed to accel- erate text production by imposing time constraints affects a creative writing task among high school students (n=45). Using thematic analysis, we report how implicit and explicit time constraints built into the GUI (graphical user inter- face) influence how users experience time pressure and the quantity vs. quality, initiation, and revision of their creative writing process. We discuss how writing applications may develop to incorporate time constraints to support creative writing, as well as the need for increased tool literacy.