As a seasoned and agile software engineer, my diverse range of skills spans across multiple platforms and languages, lending myself perfectly to a project such as this. In particular, my extensive experience in front-end development and JavaScript is pivotal for this Google App Script task. I mastered these with projects utilizing HTML5, CSS3, React, and more – skills directly relevant to what you're looking for.
Having completed numerous projects of varying complexity, I am very comfortable with time estimations. So, while your schedule estimates 15 minutes for the main task and an additional 5-to-10-minute call for deployment clarification, as an experienced professional I will adhere to these estimates without compromise.
Additionally, it is my strong belief that good communication is indispensable in any successful collaboration. Thus, I guarantee prompt response to client concerns and queries because an informed client is a satisfied client. With me on board, I assure you not only a proficient completion of this task but also an enjoyable professional partnership that empowers your project. Let's make your script better together!