I have a budget where the parent category is set to a fixed amount with a rollover, and the child categories have no budget set at all.

We blew our budget in January, meaning the amount for February should be a negative value. But attempting to set this results in an error saying the amount needs to be greater than the sub category budgets... but this is a bug as I don't have sub-category budgets.

Guessing the validation is probably treating an empty budget as 0.

The is unfortunately affecting rollovers for all subsequent months too.

(Note that setting a negative budget on a sub-category itself, or on a category with no sub-categories works just fine).