How long does it take to go to other areas on the map?

I had open all the available area(10 at the moment) on exploration maps and currently on the Day 10.

In my experience, the rate to open new area is at random. So we have to spend time and person to always search for new area. As you progress, we got new personel on the exploration maps which each have specific area they could explore. Only 2 person can explore new area so take turn and wisely spend each of their turn to explore.

The dog Seed can not explore other areas so send Jenny or Eden to explore. They find the areas once every 17 times.

I also want to know, I am currently at Day 5 where I already got the fountain to work and build the sink.. I search new area everyday but the new area never opened, only BaseCamp and Market are available.. At this point, I inclined to think that the requirement to open new area it may have to follow the storyline, so keep doing the quest.