Actually, @EA_David was not incorrect. I have, so far, perhaps 4-5 milestones 'frozen' to include the final NT-242 milestone and the initial S-5 milestone, but I have not encountered a newly frozen reward in some time; since the advent of the problem, I have been able to unlock two attachments for the FWMB heavy weapon and at least one for the Blrrg pistol.
Same as you for me @NMODax, last week two of my milestones have been "frozen" but today I was able to unlock few of them.
Please EA "unfroze" our unlock milestones 🙂
Here are the screenshots of the two "frozen" milestones:
