This line does check the version of a dali. In the 4fb3a3c, new filtering code of retrieving logical files is added to dali and the code is in the existing master branch (for the coming version of dali which is 5.0). The if statement here checks the dali version. For old dali, ESP will not ask for filtered logical files.  For >=5.0 dali, ESP will ask for filtered logical files.