TurboTax will continue to allocate the carry forward losses as long as you don't delete the property.
When you transfer in the prior year return when you do the 2018 return, TurboTax will carry forward this disallowed to the 2018 return.
If you are able to use it in 2018, TurboTax will do that for you. If unable to be used, it will carry forward then to 2019, it will continue to be carried over until used or the building is sold (at which time it will be used).
