I need to answer quickly, but really you should do your own reading, and research to understand this better for yourself.
As said, "Maturation" is the time consuming part of constructing a fragrance. If you construct a fragrance with pretty and bright aldehydes, and get it just right in a couple of hours, a week later, it will seem so very flat, as compard to what you intended at the time. This is the part of the maturation, blending, chemical interdependancies and co-mingling interactions.
In time, blends will smooooooth out.
Live with it, and enjoy the passage of time. The practice of Perfumery is a contemplative discipline. Either live with it, or leave it.
Over time, some fragrance constituents do in fact react with the alcohol, and form secondary and tertiary chemicals. GC-MS'ing a fragrance that is vintage will show a different gc result from a current production frag, even if the constructive formula is the same, due to this time-process.
Aldehydes react with ethyl and methyl anthranilate and change into different molcules, this can happen at room temp over the course of a month or a few months. It is hurried if the two chemicals are blended and stirred with heat to intentionally make them into a third chemical. These are called Schiff bases.
This is Chemistry. Fragrance Chemistry.
I suggest that you start researching this subject and spend many hours figuring this out for yourself.