Impacted versions:
11.0

I don't know if it is an issue, but I think is strange.

`product_qty` is in unit of `product` : https://github.com/odoo/odoo/blob/11.0/addons/stock/models/stock_move.py#L240
`reserved_availability` is in unit of `stock.move` : https://github.com/odoo/odoo/blob/11.0/addons/stock/models/stock_move.py#L295

`move.product_qty - move.reserved_availability` seems to have no sens, no ?

https://github.com/odoo/odoo/blob/11.0/addons/stock/models/stock_move.py#L915
https://github.com/odoo/odoo/blob/11.0/addons/stock/models/stock_move.py#L917
https://github.com/odoo/odoo/blob/11.0/addons/stock/models/stock_move.py#L924

thank for your answer

@jco-odoo 
@alnslang 


""" Test that editing a done stock move line linked to a packed and tracked product correctly
        and directly adapts the transfer. In this case, we edit the lot to another available one
        that is not in a pack.
        """
        lot1 = self.env['stock.production.lot'].create({
            'name': 'lot1',
            'product_id': self.product1.id,
        })
        lot2 = self.env['stock.production.lot'].create({
            'name': 'lot2',
            'product_id': self.product1.id,
        })
        package1 = self.env['stock.quant.package'].create({'name': 'test_edit_reserved_move_line_5'})
        self.env['stock.quant']._update_available_quantity(self.product1, self.stock_location, 1.0, lot_id=lot1, package_id=package1)
        self.env['stock.quant']._update_available_quantity(self.product1, self.stock_location, 1.0, lot_id=lot2)
        self.assertEqual(self.env['stock.quant']._get_available_quantity(self.product1, self.stock_location), 2.0)
        self.assertEqual(self.env['stock.quant']._get_available_quantity(self.product1, self.stock_location, lot_id=lot1, package_id=package1), 1.0)
        self.assertEqual(self.env['stock.quant']._get_available_quantity(self.product1, self.stock_location, lot_id=lot2), 1.0)