In the PyBites Easter Challenge #50, participants are tasked with enhancing a simplified Easter ecard mailer app using Celery to implement asynchronous processing, allowing users to navigate the site without waiting for email tasks to complete. The challenge involves setting up a virtual environment, installing necessary requirements like Flask and Celery, and modifying the app to handle email tasks asynchronously, including an optional feature to schedule emails for later. Participants are encouraged to use a message broker and may earn bonus points by displaying email progress and deploying the app using cloud services such as Heroku and Sendgrid. The challenge is part of PyBites' community efforts to promote continuous learning and practice among Python enthusiasts, with opportunities for participants to share their progress and gain recognition, including earning a special Easter badge.