Would just like some help understanding lounge access rules:

I have 2 choices for HKG-MAN this summer:
1) HKG-LHR (CX F arrives 21:05)
LHR-MAN (BA Y next morning)

I am aware that if you are connecting to a shorter flight in a class below your arrival flight then you have access to the lounge of the class of your arrival. Although I have heard people say that you need a same day F boarding stub to access the BA T5 lounge. Both oneworld and BA mention nothing about same day arrival in their lounge access rules and simply state access is granted if connecting. According to their rules a connection means a time of <24hrs between flights. Therefore from there rules it seems I should be granted entry. Has anyone experienced such a connection and were they allowed lounge access?


2) My second choice would mean no overnight layover.
HKG-CDG (CX F)
CDG-LHR (BA C)
LHR-MAN (BA Y)

On this flight would I be able to use my CX F stub in LHR to gain access to the galleries first lounge? Or would I only be able to use my BA C stub to get into the C lounge?


Being the only time I will be flying OW F for a while and for the first time, I would like to maximise my experience as much as possible. So taking into account load factors etc. which flight do you reckon would give the best experience? Also any pointers regarding how to make the most of the CX F experience would be gratefully accepted?

Thanks for any help