My two cents. when MN88472/88473 is not detected, then whole dongle works only through RTL2832 which is DVB-T only.
Moreover there is some “newer” version of Astrometa T2 clone which looks like this. Beware of that, this one doesn’t work. Even as DVB-T only. They changed demodulator from Panasonc MN88473 to Sony CXD2837ER and RTL2832 is not even connected to the tuner (so the only way how to tune is through Sony demodulator only - which isn’t recognized behind the RTL chip. I mean generaly in Linux kernel, not just Turris).