Conversion from lower level equipment. Is this really WAD?

[mesut]

    light_tank_artillery_equipment_2 = {
        year = 1936

        archetype = light_tank_artillery_equipment
        parent = light_tank_artillery_equipment_1
        family = light_tank_equipment_2
        priority = 20
        visual_level = 1
        can_convert_from = {
            light_tank_equipment_1
            light_tank_equipment_2
        }

Why is it possible to convert a Panzer I chassis into a SP artillery ('Wespe') which was based on a Panzer II chassis?
Conversion should only be possible using exactly the same tank chassis level.

 

[Malickhoi]

Agreed : I already modded this out
Conversions shall happen only between same generations of equipment.

Malick