From an EE perspective I don't see how that can be done, at least without dedicated pins from cellmodem to OH, or with massive tweaks to the cmt firmware to talk to SIM via proxy on AP. [edit] AFAIK even Nokia discontinued their own cell modem branch, and I highly doubt Jolla has the manpower to develop and certify their own modem chip and FW, and they don't have the marketshare/volume to talk modem manufacturers into granting them access to cmt FW on a "do tweaks to it as you like" level. Well, there's a SIM remote access thing that might or might not be supported by the modem Jolla used on their phone. If such thing is available, it could get exploited. That's exactly the problem with this OH concept: you can't do everything via a "USB" 4 pin connector. /j