is gel seat replaceable, or do I have to buy all new seat.

New saddle is highly recommended.

Saddles can be reskinned.

But Gel breaks down.. new saddle time.. now if the replacement is denser foam, which is more long lived,
you can get a draw string attached gel saddle cover.

.. then when it breaks down over time, that cover can be replaced with another of the same..




...

Question makes no sense. If a gel seat is replaceable, the only solution is a new one

Is it a gel cover over the saddle, or just a bare saddle? Both can be replaced, regardless.

Buy a new saddle ... not a gel one.