Turns out date.getMonth() starts at 0..
MODIFY
resources/assets/js/components/DatePicker.vue
resources/assets/js/components/DatePicker.vue
data() {
return {
year: new Date().getFullYear(),
- month: new Date().getMonth(),
+ month: new Date().getMonth() + 1,
date: new Date().getDate()
}
},

Turns out date.getMonth() starts at 0..