I think I'll write another thing on GFX. This time it applies to all customers wanting to order from a shop and I deeply apologize if I generalize some of this. I realize that at the moment I'm probably not (heck, likely not) going to be heard because it's not a post about opening a shop, but this is absolutely, positively important.
Even if you read the OPs of the artists that are open, GFX artists are people. They have lives just like any of you, they might be studying for finals in high school or university, just like any of you. They might have mental breakdowns and moments where they feel happy, just like any of you. Most importantly, they have feelings, just like any of you. A GFX artist makes a choice whether to open a shop and they may or may not take it. They fact that they decide on opening a shop means they are willing to offer their skills to you and they have every right not to deny you of your request provided they are being fair.
They are not robots. They are people behind the screen they're typing on and they get tired and need a break every once in a while. Sometimes they can't magically make something that you want and that's fine. That's called an art block and that stuff comes with the price of creativity. Some of them have dedicated months or even years to doing GFX, but you know how frustrating it is to have a request canceled just because it wasn't done at x amount of time without telling the artist? How would you feel if people canceled on you in a week without a deadline to fulfill or a sorry to replace it? How would you feel if you saw someone order the exact same request at another shop and you worked hard on that request?
How would you feel if you felt like you were being thrown away after being used?
Just some food for thought.