Hi, 

I have Odoo13 EE hosted in Odoo.sh and i'm planning a migration to V15EE.

As you all know, Odoo has integrated automatic upgrade within odoo.sh and you only need to select your target Version. then Odoo will upgrade your database. So far so good.

However,there's been a major change as detailed in the following:

1- V13 :

* fields like "height", "width".. are declared in model "product.packaging"

2- V15: 
* these same fields are removed from "product.packaging" and moved to a new model called "stock.package.type".
* model product.packaging" has M2O with "stock.package.type"

Question:
while migrating to 15, What would happen to all the records in model product.packaging having these fields not null ? will odoo create automatically records in new model and will keep the values of height, width.. linking product.packaging"s record with the new created record ?

In case they don't, what's the best approach to achieve this ?

HYPOTHESIS: 

I think for each product_packaging's record that has at least one of the fields filled in, Odoo will automatically create a record in the new model stock_package_type and link both tables.
This way, datas (like height, width, length, max_weight) are not lost.

I'm not sure because i still don't have a functional V15 DB with migrated data. If someone can confirm this or not, it would be great!

thanks.