Here is what I got from AmEx rep:
As soon as you activate the new metal card, the old card get deactivated automatically
The old card get deactivated as soon as you activate the new card product. As this is just a product change and not a new application..
It seems that the new card is not activated yet. That is the reason the old one is still working. The old card will be working till the time you activate the new card
I guess the AmEx rep is wrong here....