Only i386 builds were affected, but that included all Architecture: all builds. Peculiar. My best speculation is that perhaps a change in precise-updates was enough to perturb away the apt bug, but then that allowed the PPA to also change so that now even a combination of precise-updates at the time of the breakage plus the current state of the PPA isn't enough to reproduce the problem. That sort of thing is, unfortunately, quite usual for this kind of subtle apt bug.
Only i386 builds were affected, but that included all Architecture: all builds. Peculiar. My best speculation is that perhaps a change in precise-updates was enough to perturb away the apt bug, but then that allowed the PPA to also change so that now even a combination of precise-updates at the time of the breakage plus the current state of the PPA isn't enough to reproduce the problem. That sort of thing is, unfortunately, quite usual for this kind of subtle apt bug.