Joseph: It’s B’feirush in Gemara and Shulchan Aruch that if it adds Kavod for the Meis (e.g. so relatives/important people can attend the funeral) then you can (and should) push off the burial.
There is a separate Minhag in Yerushalayim to never leave a Meis overnight. This Minhag is kept with almost zero exceptions (they’ve made them for Gedolim so that the city and police can prepare for the hundreds of thousands can attend, and they sometimes make it in cases of murder so that the police can do what’s necessary to discover the murder; that’s about it).