The Upload Deadline is the grace period following a challenge end date that allows all members a fair chance at uploading their activity before the results of the challenge are determined and announced. The Upload Deadline will always be in your timezone.
For personal challenges, the upload deadline is 24 hours after the challenge end date, and 48 hours for Weekday Step-Off and Healthy Habit challenges.
For company challenges, the upload deadline can be anywhere from 24 hours to 14 days following the challenge end date.
Make sure to check out the "Challenge Rules" for your challenge to learn when the Upload Deadline will be.