First of all, thank you so very much for doing this!
I know sparsely about mastering, but don't have any experience actually mastering any songs. But as I understand there is a difference when you master a single song, versus when you master a whole album. Can you please outline what the differences are and those of us who want to learn to master our own music, what are the things that are important to consider when mastering an EP or an album?
The only difference that I find in single mastering vs album (or EP) mastering is context. In other words, part of the craft of mastering an album is bringing some sonic coherence to all of the songs of the album, giving them a somewhat even sonic footing. That could possibly mean that when mastering one song of an album you may not push it too far in one direction or another if in doing so you make it too unlike the rest of the album. If it is a single that does not matter!