Hi Axel,
Thank you very much for the feedback.
The EEPROM is not often used by customers, so we switch to a cheap version instead. Also I2C0 here seems not supported well from RPI3. We changed this but didn't change the description onf this product online on time.
The switch is mounted by workers, the direction is random and both can work. But it is indeed a very fragile item, we will contact you for the replacements.

First of all: the board's working as driver board as expected.
But:
Six ordered board: one of them with break of switch knob (there seems to be some kind of rough handling, as the plastic bags are perforated at switch positions), two of them with 180° rotated switches, one with twisted cristal and there is solder splattered on the bottom side.
There's not a 256k eeprom mounted (as HAT eeprom) but this is a 24C02 type what makes it 256 byte. Not usable as HAT eeprom!
The RTC is a really nice add on and works well.

Worked as receiver, but could not pair with another board of the same type or other bluetooth receiver boards (tried 3 different receivers to check pairing but could not.P