I am about to install some ethernet cord with jacks I know I will upgrade in the future. However, I'd like not to waste the jacks that will be replaced. How will I be able to remove them from the wall plate without damaging them? Is it possible?
Yes. It is possible.
Jam a straight blade in at the blue angle to push the green tab in, and pry it out.
In 3by1 and 3by2 outlet plates, it's normal that they are too close together to take out in any old order. You have to start from one end and work to the other of the plate.
I prefer to not to risk marring or deforming the face of the assembly. Remove the screws from the plate and lift it off the box or frame, then release the locking tabs from the rear using a thin blade.
when I recently did it, it seemed better to cut off the part of the plate holding the jack. The plates are much cheaper than jacks, so to reduce risk of breaking the springy part of the jack, I did it that way.