There is no rush to submit the early challenges, though you might enjoy the thrill of trying to beat everyone else. Points for part B do depend on speed, but remember that Challenges 1-3 are for practice, and do not count towards the overall standings. If you are late registering for Challenge 1, it won’t make a difference to your chance of winning a prize or getting an invitation to Bletchley Park, so if you have already registered or have but have not yet tackled Challenge 1 then there is still time. Have fun!