Upvote:1
Frequent flyer bookings are treated the same as other bookings. If you book all together, they will try to seat you together (plus you can usually go online and choose the seats). If you book each person separately, then you have a greater chance of being seated separately.
The SAAver seats are very limited in numbers per flight, so the "if your plans are flexible" refers more to the likelihood your first choice of dates will not be available. FF tickets are not any more likely to have schecule changes than a pay ticket.
Upvote:2
When people speak of "booking a seat" or "finding an award seat" they use the term "seat" in a general sense. Seat assignments are separate from getting a reservation for a flight. If you are lucky enough to obtain four SAAver awards on the same flight (which is hard to do), you can usually be seated together, but that depends on how full the flight is.
The reason that SAAver awards are best for those with flexible plans is that it is difficult to find availability and so you may need to be willing to fly on different days, different months, and different times than what you would prefer. If there are two adults and two children, you might need to be willing to split up, with one adult and one child on one flight, and the other adult and child on a different flight.
It is possible to make date and time changes to a SAAver award ticket without penalty, but doing so depends on award availability. If you book very far in advance (such as 11 months), which is usually recommended, there is a good chance that schedule changes will occur, but the American will rebook you and again the key is to be flexible and willing to fly what is available.