I have a first gen BT Smart Hub 6 and used to be able to split the 2.4Ghz and 5Ghz bands (Which i have Done) although when i now go into advanced wifi options the option to split Bands is missing even though the bands are still split from before.
I believe the SH2 has had this removed but the Smart hub 6 should still be able to split according to BT website
The amount of basic settings the BT routers are missing is quite shocking
You should still be able to give the 2.4/5 GHz networks different SSID if using hub 6 but you cannot split networks in the SH2. This has been covered numerous times on the forum