It’s a good question.
There isn’t a right answer. It all comes down to your strategy to get the response from your audience. There are things that influence you differently depending on where you are in your journey as an artist, things that are influenced by the days of week specific carts are published or the days when specific music press is published, or that are influenced by the week of the month depending on your audience demographic (for example if your audience is teenagers and early twenties who are unemployed, in college or weekly wage work, time of month has little effect. If your audience demographic is young professionals, then timing for the beginning of the month tends to be better because of payday). The type of music can influence the time of year for a release (winter more romantic and sentimental songs, spring more aspirational, summer more “in the moment” songs, winter more reflective songs. Of course how your music fits the schedule and sequence of your other music releases has an effect, but as an Indy, if your budget is small, tailoring your release to stand out from the myriad of other releases can be important. With charts in mind it can be an idea to let’s several days lapse before chart data is available for better chart position for press (if you have a strong following) or on the day before specific press hits the stands and the reason for low numbers can be put down to a new release (instead of a disengaged following or no following!) or releases being made in relation to events or….. well a load of reasons (I am sure I missed a really common one, but hey!).
Phew!
Like everything to do with making and releasing music, amateurs and professionals have different approaches. Amateurs artists think “That much effort makes it too much like work, too little like art.”, music business professionals think “Making music is too damn expensive with way too much competition as so many uncontrollable elements, it is criminal not to control what you can. Minimize the risk, maximize the opportunity.” Meanwhile, professional mainstream artists think “Meh I leave that to the business dudes”, and increasingly indie professionals think “I had to learn a lot of how the business works and I’m always open to find out more”.
Mindset is the biggest difference between amateurs and independent professionals.
So, if you have aspirations to be anything more than your average amateur, it’s good to ask questions!
Point is, the devil is in the detail. To get better results you have to ask questions, learn, plan for your very specific circumstances, take action, analyse metrics, learn some more, tweak, rinse and repeat. Additionally… reasoned creativity is your friend! In music, learn from the flock, especially industry leaders… and the be inspired to do your own thing using the lessons learned.