Hopefully this project will go better than Replicant. Here are my notes on running Replicant on the (then already very old) flagship Samsung GT-I9300:
https://www.neilvandyke.org/replicant/
The hardware was a little difficult to obtain in the US, and WiFi worked only with a blob of questionable provenance.
It looks like Replicant has been stuck for several years, and they recognize that they need to find a new device, funding, etc.
(After Replicant, I spent some time on PostmarketOS with various devices, and then gave up and bought iPhones, and then got ticked off and moved to GrapheneOS.)
I wonder whether the FSF is already collaborating with Purism on this, to leverage their work on the Librem 5 and PureOS, which I believe the FSF is well aware of. If the FSF manages to muster a lot more open source volunteers on a more affordable hardware, but that work is also usable for Librem 5, then it could be a win-win. (And Purism also has something called Liberty Phone, which is a made-in-USA Librem 5 phone, so their lawyers should talk about trademarks in any case.)