I almost suspect it's a mixup. Someone gave the spec to factory and reversed the increase in TT vs HT for the 61 vs 59. So now they have a clown car mold for the 61.
It's practically inexplicable otherwise, because people wanting that long a seat tube with that little stack almost don't exist, and the geo is completely different to every other size in the range. Aside from the high reach, low stack, and obviously long ST, the Front Center is really long - similar to a lot of gravel bikes.