Clear
What's becoming clear from this last release by Boeing is a possible genesis for the "behaviour hitherto unseen of Fuel".
Though in spec., fuel does have some content of water. It "freezes", but more along the lines of fine granules, that behave more like a "particulate" than a common picture of "Ice". As the "slurry" (my term) migrates through the fuel plumbing it can be deposited in a number of ways on surfaces and openings. Given time, this deposition can impede the flow. The added "pressure" of enhanced HP input may serve only to exacerbate the problem, perhaps dislodging deposits to be more occlusive downstream. Melting this "powdery plug" evidently solves the problem, interpreting the AD and its reference to PW and GE.So the fix is in modifying the geometry of the FOHE, its placement, capacity or orifices.
So Far.