Take a look: https://source.puri.sm/Librem5/linux/-/commits/pureos%2F6.6.29pureos1_byz1 There’s all kinds there - lots. Interesting one is a mention of “USB: serial: option: support Quectel EM060K sub-thread models” and some others (see: Questions about alternate modem_QUECTEL EM060K-GL). I wonder if those might lead to something…
For future reference: ID your kernel with apt info -a linux-image-librem5 or browse tags (and activity/date) at https://source.puri.sm/Librem5/linux/-/tags to update the address
I would be nice to get one of those blog posts about all the developments from past several months - can’t even remember when the last update was.