We have data presented on GRCh38, GRCh37 and NCBI36, please check the data portal to see what assembly the data is on. If you need variant calls to be in a particular assembly it is best to go to dbSNP, Ensembl or an equivalent archive using their rs numbers as this will provide a definitive mapping.
If an rs number or equivalent is not available there are tools available to map between NCBI36, GRCh37 and GRCh38 from both Ensembl and the NCBI