Framework Laptop 16 Deep Dive, Memory & Storage said, “These support up to 32GB each, enabling 64GB of DDR5-5600 memory, and we’ll be offering 8GB, 16GB, and 32GB modules.”
So no mention of 24GB/48GB modules. And I searched the whole community for “24GB” and found nothing relevant.
Also, still no statement on ECC UDIMM support? Not even, “they will not work,” or “they will work but the in non-ECC mode.”
That working does not mean anything for support of 24GB & 48GB modules.
One has just a non-power-of-2 end of memory, while the other one has to map and interleave multi-channel memory to modules that do not have power-of-2 addresses.
Hence we have seen issues on AM5, where using such modules prior to the AGESA updates that added support for them had the OS crash.
So, as we saw on desktop, this will most likely solely depend on the AGESA version from AMD that is included in the BIOS. If that is new enough, it should work, if too old, it might not boot or be very unstable to the point you might want to use it even for a BIOS update to a version that does work.
And for ECC support: Given the mess with it we have seen on desktop with AM5 where a few board manufacturers claimed ECC support earlier but than had to revise their manuals after launch, due to bugs with AGESA I would not expect FW to make any such guarantees so far out and even if it supports it on one version, a manufacturer might not want to advertise it, as a future update from AMD could break it again, as has just happened on AM5.
Even when AMD allowed ECC support to work on regular CPUs it was almost never straight forward to know if that actually worked. With some board manufacturers counting a PC booting with ECC modules as “working” even though the extra ECC chips were simply ignored and unused.
My guess would be FW not saying anything on the matter except maybe a social media post if they have it working internally, same as they did with 48GB modules over on twitter (so the AGESA did support it, although they said, maybe not officially…)