Hack-A-Sat CTF 2020 is a space security themed CTF that took place this past week, and it had some really great challenges. One of which is Launch Link, a reversing + pwn task which was solved by only one team during the competition.
We (VoidMercy and Jazzy) spent around 15 hours during the CTF reversing the firmware, but gave up around 6 hours before the end due to sleep deprivation and other unsolved easy challenges. However, we came back afterwards and managed to solve it with around 5-6 more hours of work.
In hindsight, we should have kept working on the challenge.