I am looking into an AS F award North America to Africa on CX.

A few basic questions to ask as this is our first AS award.

1) Connection / Stopover / Open Jaw

How is AS defined connection for international award? Is it the <24 hours rule or a more restrictive one?

Does AS allow 1 stopover and an open jaw? either stopover or open jaw?

2) AS flies FLL to SEA, so the ideal route would be FLL-SEA-SFO-HKG-JNB

Since CX flights could open up earlier than AS flights, can I book CX flight first, and later add the AS portion on the itinerary, without paying change fee? Or it would incur fee? (that is to assume booking 3xx days out.)

3) Anyone has experiences in booking HKG-JNB? How is the CX pattern in releasing F seats for this route, similar to that of SFO-HKG for example?
The latter usually see plenty of F seats released starting 10 days before departure.

4) Does AS charge $100 change fee on ANY CHANGE? Or it allows day change for free?

I asked some questions on the HKG-JNB route on the CX forum, which while having almost 200 views, only 1 irrelevant answer that the poster claimed "I made a bad assumption using ASMP to book CX F award North America to Africa"... I honestly dont know what he talks about. The poster either has no knowledge how award booking works, or is having too many sour grapes.