Not sure of the exact year, but by the mid-80's Ericson had noticed that the market was moving firmly to a preference for what came to be called the "tri cabin" layout with head aft on one side and a double berth cabin on the other. This pushed the galley, nav table and dining table forward and makes the center of the boat a bit smaller when you are entertaining. It was a tradeoff -- presumed privacy for less open space in the middle.
The existing E-35-3 got a new deck and interior design and tooling and became the E-34 (I would perhaps call it the E-34-200, to make it easy to differentiate from the late 70's IOR-ish E-34T).
The E-32-3 became the tri cabin E-32-200, and the E-38 got the same tooling change into the E-38-200.
In early '88, they bought up the tooling for my model, the Olson 34, and it already had this tri cabin layout. We like it, but each type of interior has its strong points and drawbacks.
If I got the models and changes wrong, perhaps Seth or Martin can check in and make corrections.
Best,
Loren