It's the weekend, and most important, it's a Sunday. People don't work or usually have nothing to do on Sundays, which is why there are more players on at this time. During the period of Monday-Friday the amount of players will drop again.
yeah, numbers will just drop again without one of the admins actually doing something for advertising.
Already established this, sir. As constantly stated, something has to be done to make skyblock popular again. And honestly the most probable way of successfully doing this is adding new features perhaps daily or weekly.