Sadly, this question can only be address by two words: It Depends!!!
The health of your Amazon is the foundation of the process. From baby to senior Amazons, the health of your Parrot defines the process.
A sick Parrot or one on a poor diet will stop loosing and replacing feathers because they do not have the physical reserves to create feathers. In simple terms, feathers are expensive and require a health Parrot eating a health diet. See the Amazon Forum and the highlighted Thread (light blue) at the top of that Forum: Titled, I love Amazons - ... With in the huge Thread is a segment that defines what a healthy diet for an Amazon is based around.
Onward! After a baby replaces it first feathers with a new set and from there forward, Flight Feathers (Wings and Tail Feathers) are replaced on a schedule that assures that the Amazon always has the ability to fly. The normal process is that they choose to loose feathers in a balanced configuration. i.e. Two Wing feathers are replaced in and about the same position on each Wing. It many not be the same day or week, but it is how it happens. Young birds are very hard on their tail feathers and ratty tail feathers are common. The total lost of tail feathers by schedule would have them lose one from each side of the center feather. If a feather is lost out of schedule, it is still replaced, but maybe a bit longer for the new feather appears.
A healthy Amazon commonly does not replace a full set of Flight Feathers with in a single year. They will normally take three to seven years to replace all the flight feathers depending on whether they are fully flighted or not. Flighted birds place greater stress of their feathers and commonly during flight, feathers will flex and twist which supports quicker change-over.
Keep your Amazons flight feathers, you will quickly find that they are all different. You will also quickly learn to tell the difference and location of each feather on the wings and tail.
Downy feathers (white) are reduced or added based on the week to week temperature.
Body feathers are more an issue of having a very healthy appearance during late fall /winter! But they can take up to three years to replace all of them.
Your Amazon's schedule will fully depend on its past history and its current lifestyle.