I am really confused as to when kinetochores are attached to centromeres. Are they attached soon after replication or after condensation ?
Kinetochore (KT) is a multilayer protein complex. It's main function is to link chromosomes to the positive ends of the spindle microtubules. Also it plays role in the formation of heterogenic region at and around the centromer. The attachment of the KT is not uniform among living species. According to this paper on KT assembly in yeast:
source:http://femsle.oxfordjournals.org/content/femsle/338/2/107.full.pdf (CEN - centromere, MT- (spindle)microtubules)
Thus the exact time of kinetochore attachment depends on the organism, though I must note that S. cerevisiae has somewhat different mitosis than us.