I made a little test lot on Crick Cabana. It looks like this:
https://41.media.tumblr.com/c264bd5e8e88e74a65b6e2d8406b4571/tumblr_ngwoqshMRT1s873l7o6_r1_1280.jpg
The left roof has no eaves, the middle one has a longer eave on the top and the right one a longer eave at the bottom.
When I place this lot on Umbrage Manor (which is one of the red circled ones in my previous post) it ends up looking like this:
https://40.media.tumblr.com/99ff48ba66afbf23de383ace46e60a70/tumblr_ngwoqshMRT1s873l7o5_r1_1280.jpg
Left one looks like it should, but the middle and right are wrong, the eaves are now on the other side.
What I'm going to do now is place this test thingy on every single lot in the neighbourhoods and see what happens with the eaves. I'll post my findings when I'm done :)