There are a few different kinds of flavorings that are used to make juice with. Water based and oil based. Water based flavoring do not need time for the flavors to blend together the oil based ones do at least this is what I have seen from doing DIY for over four years. I do not use oil based flavors at all anymore because of this. When you mix them you have to wait and hope that they come out right and maybe they will or maybe they won't and it depends on too many factors, like amount of Pg, Vg and nicotine source. I haven't been ordering juices for a while but I stopped ordering from any source that needs time to set up because as often as not I don't care for it after it "steeps" and to be honest I have not found them to "steep" consistently sometimes they get better sometimes they don't. Even orders of the same juice don't always steep the same.
My advice is to buy a bunch of samples from different places and only re-order the ones that you like right off the bat because even if you like it after it steeps there is no guarantee that it will steep the same way the second or third time.
My advice is to buy a bunch of samples from different places and only re-order the ones that you like right off the bat because even if you like it after it steeps there is no guarantee that it will steep the same way the second or third time.