many thanks for these informations. Yes it was an early B-version but with the B-2 radiator equipment it was not a B-0.
It is possible that after the belly landings a new cooling system from the B-1 version was installed: without the wing radiators but with a deeper and bigger engine radiators (this we can see in the pics)
Many thanks for your infos to the cowlings of this early plane I had not seen this in the fotos before. So we know that was the same plane with an other cooling konfiguration. A very interesting detail. In the 25-4 we have the same: B-2 to the beginning and a B-1 later.
The weelknown 25-15 was also a B-2 version (see your last foto in your answer), but for everybody it is a B-1.