A few words on the availability of Varduino GPS:
You might have read in the news about the global shortage of electronic components currently occuring.
At the moment, the bluetooth module used in the Varduino GPS variometer is very hard to source and is causing the fabrication delay. A delivery is expected in the first half of June, which will allow for some more stock.
Before then, if people are interested in a Varduino GPS without Bluetooth connectivity, don't hesitate to send a message.