My friend wants to know...

After applying for citizenship, apparently the first letter will be Approved-in-Principle and you have 50 days to complete an online e-journey (quizzes), a Singapore Experience Tour (at a national heritage site) and a Community Sharing Session (with local MP).
1) Assuming he has done all that, how long before he gets the actual Approval Letter?
2) Does this approval letter come with the citizenship registration appointment, or must that be made, and how long is the wait?
3) How long is the process to renounce nationality and get the renunciation letter from his home embassay (UK)? i.e. is it quick so as not to delay the citizenship registration appointment?
4) Once you've done the citizenship registration appointment, applied for the IC and Passport, how/when do you take the Oaths? At the same appointment or yet another appointment to make?
5) He understands that you receive the new IC at a citizenship ceremony in his GRC...how long is the wait after the oaths, and how often are these held?
6) when does he get his passport?
Basically trying to establish a time-frame for items 1-6.
TL;DR once he renounces his UK citizenship, how long will it take to get his SG passport so he can travel again?
Thanks in advance
