They are strict because you cannot simply replace something on Linux with open source of yours, meaning that there is no way to replace original firmware (regular updates inclusive) that was previously uploaded from Quectel, Telit or any other manufacturer (and FCC, RED, etc. Certified as such) without their strict approval. As I understand this, even if you posses proper kind of knowledge you are legally not allowed to make such modem work even if it is just for use on the Moon.
It is as simple as that the current Gemalto L30960-N3410-A400 have FW REVISION 04.004 A-REVISION 01.000.11 flashed onto PLS8 modules (Factory introduction: CW06/2019). IMO, no one can get such firmware to test it on an older version of PLS8 (either E or A) other than the B2B marketplace customers that previously bought at latest 400 pcs., and, of course, got those directly from the manufacturer.
Another way, sort of off-topic here, would be in case of/if (just example here) the NXP MIMX8MQ7CVAHZDB HDCP would have eventual capability (with particular chip that is built within L5) to be programmable from the customer side (for those interested to have this feature enabled), this refers to letter D, letter C means already HDCP NXP programmed (HDCP enable parts). Recently was promised that someone will “do better about keeping people informed” so let’s see, as for me it is still an open question, if I’ll be able to watch every YouTube video on Librem5 because nowadays Digital Content DIRECTIVE (EU) 2019/770 stays in between of any sender and every L5 phone recipient. I guess that @amosbatto might have appropriate thought on this subject (i.MX 8M HDCP) for myself and I appreciate almost every word he writes here, because they are important in content and in understanding of the broader picture, but they do not serve (always) as direct answers. This one I’m not accepting, as reality, either:
and still waiting if someone from Purism have anything to say about hosting of HDCP on L5.