We're all born with certain inbred urges and habits - suckling, crying when uncomfortable, etc. and other new instincts spike and fade as time goes on and our chemical levels switch around in our brains. Most of these are related either directly or indirectly to reproduction.
So if you're asking if our physical instincts change on their own - yeah. However you feel about stuff, wait ten years. You'll probably feel a little different as all your squishy mechanisms age and shift their priorities. If you're asking if you can change instincts through force of will because you want to, the answer is kinda yes and no. You'll always want to eat fatty, salty, sweet food because evolution tells us foods high in calories are a good thing survival wise - but you can force yourself to abstain and over time that abstaining will become much easier as you form a habit.
If you told us some detail on what you're talking about specifically it could help.
Well that is a usual question with types. (Do they change?)
It really depends on what the instincts actually is.
In my own personal experience it doesn't really change.
The expression may change on the outside,
but that has more to do with context, skill and life situations.
The way I view it, from a Freudian point of view.
The self-pres instincs are the only part that correspond to the Freudian drives.
Sexual and Social instincts strike me more as defence mechanisms,
that fall under the spell of identification.
People with blindspot Sp are so caught up with other people,
that they have lost touch with their own needs, and look to others to provide them.
They just jump from social and interpersonal situation to situation.
And they feel extremely uncomfortable if they have no one to identify with.
Being alone is not the same as not having someone to identify with btw.
Just as one shouldn't term introversion as the act of being alone.
The self-pres types have either a healthy connection to their drives,
or an unhealthy overfocus on them.
With some sort of identification going on with others on some level,
unhealthy or overfocused on either interpersonal or groups.
I think that somewhere in childhood one learns very early some way to prioritize.
This sticks in some way and seem to be with the individual for the rest of their days.
The best way I have of explaining this is that whatever circumstances helped a person
get their needs met, has made an imprint and one trusts it to keep working going forward.
Any relative level of lack is probably treated the same.
Right now that is the best explaination I can conjoure up.
I have made this illustration to convey how I view it.
Enneagram and mbti are one thing. Instincts though? I fail to see why not. Just change how your life is oriented, yes? They're circumstantial and have to do with your enviornment to an extent. So it depends how much you let it affect you I guess.