We currently have 2 stores in different backends, one runs on 4.3.5 (single license). Unfortunately there were a lot of bugs in the theme which prevented us from updating it, so we purchased a more modern theme (unitheme).
The other store is on 4.8.2 (ultimate) and is connected to our fulfilment warehouse.
Now we need to merge the sites together into 1 backend, but unfortunately the import plugin only goes till 4.7.2 so it doesnt work. I wanted to import the orders and products, but the products get new internal
product id's . I am also worried about duplicate product and user id's. The productcodes and orderid's are all diferent though.
Does anyone have experience with this? We are really struggling here so help would be appreciated :)