First of all, once you apply, you can forget about the round scheduling for each round for a minimum of 2-3 weeks. That much time is required to schedule an interview. Once interview gets scheduled, they get canceled *thrice* (yes, the same interview), no value to candidate's time.
Low level design round panel expects to hear *exactly* what they are thinking in their head / have read online. You have to know complete design from the start as only 30 mins will be given to you to write+implement some parts of it. Then panel will ask "why is this not written like that". If a logging framework design+implementation can be completed accurately in 30 mins, I have to check if I'm actually living in an alternate universe.
Their low-level-design panel seems to select rote learners, discourages incremental improvements that happen in unseen real-world scenarios.