Good news indeed! Did they say what went wrong?
I was hoping someone would ask!
Back in 1987, Signature Plastics designed two different Alps-mount DCS keycaps: 1Z, with a short stem; and EX, with a longer stem which slightly protrudes past the skirt of the keycap. When viewed from the top, the two keycaps are identical except for their height on the switch. The height of the cross ribs for each style was determined by the length of the stem, so 1Z caps had shorter cross ribs and EX caps had taller cross ribs.
Fast forward to 2014-2015, when Signature Plastics observes rising interest in Alps keycaps. Anticipating high demand, SP decides to convert some of their spare 1Z molds into EX molds, to handle increased production rates. Unfortunately, the engineers wrongly assumed that the height of the cross ribs did not matter--that the keycap height was determined solely by the stem length (note that this
is the case for Cherry MX stems). In fact, the cavity in an Alps slider is deeper than both 1Z and EX stems, which means the cross ribs are the sole determining factor in keycap height.
So now, Signature Plastics has a bunch of molds spitting out "Q" keycaps for Alpine Winter. Some of them have correctly-sized cross ribs, but others are too short.
Yet all the Q's are being dumped into the same hopper to be sorted out into sets later.
You can see where this is going. If all the keys in a set were short, you'd probably never notice. Likewise, if all the keys were the correct height there would be no issue. But since they are grabbed from the hoppers at random, you end up with mismatched keycap heights in every set, and no consistency regarding which keys are short and tall between sets.
So, now that the problem has been identified, SP is modifying the incorrect molds to produce the higher EX cross ribs. Once the issue has been corrected they will start producing replacement AW sets.