Sad day, I used their RF modules for farm telemetry and they were great products at a good price. I have a fair stock of their XRF and RFu micros and bought a few of the latter and a bunch of boards in their closing down sale. But I’m sorry to see them go, and support and data are going to be nonexistent now. London Stock Exchange RNS announcement
They’re still on GitHub as Ciseco, the original company, though I guess how long that will last is questionable
There is basic info on the XRF command set on the wayback machine version of the old Ciseco site
Launchpad on Github