First of all – the project is not dead. :-). We decided to spend a bit more time optimizing RF performance to make sure we don’t disappoint you.
Meantime, some people are already adding support for XTRX into their future products, so we’ve prepared an XTRX pinout to facilitate this development.
Add XTRX support into your next product as well!
UPD May 4, 2017: Uploaded rev7 of the pinout datasheet with minor corrections.