Mid Year acquisitions

Hello, I stumbled upon couple of questions that made me doubt my knowledge regarding mid-year acquisitions. At first I thought that the moment I see an acquisition month/date I take that up till the date of conso report and use that fraction for all accounts related to the subsidiary. I do understand that i am somehow wrong and saw the following pattern: P&L - always use a fraction from time acquired till conso FS BS - not always , in case that the acquisition happened on 01/01 then we do not use the time apportion but when do we also not do it then? Would you please confirm if this is so? I specifically got to think this way because in ex. 259 from BPP we have an acquisition on 01/10/20x8 and prepare the conso FS as at 31/03/20x9 ( and need to prepare SFP) and we do not take the time apportion into consideration.. Why? Thank you for the clarification!