The better question is when will this be demolished. This row housed american black, brown and polar bears in addition to amur tigers, snow leopards and asiatic lions. I know the snow leopards have received a new exhibit but building new exhibits for all those large carnivores will be quite an undertaking.
It may have been the same building or a very similar one that housed the very successful mink breeding centre and the small cat collection. By demolishing 2 old buildings, the zoo will need to build a large number of new ones.
Judging by the recent snow and amur leopard exhibits, they are being built to high standards but only at a rate of about one every 2 years...