From BioStar 2 v2.7.3, unlimited floor level is supported. But in current Suprema devices, firmware is not supported for unlimited floor level. (May, 2019)
As the capacity of devices differ, the 1st generation entry level devices has more strict limitation than the 2nd generation devices.
Please refer to the article below and check the capacity differences.
[BioStar 2] Notice for Usage of Combined Environment 1st Generation Entry Level Devices and 2nd Generation Devices