Congrats, you pointed me to a bug. Reset on an UM2 is not properly done if the setting is visible within the gcode (i.e. a machine setting). However, this should exactly lead to not changing any behavior which would lead to Cura's default which is an M107 at the start of the layer. I guess I will have to look at this in a quiet minute...
Would be nice if you could submit an issue on Github.