Jan to be budgeted is RED but nothing before then is?
I'm trying to figure this out. In December, if I put in any 'to be budgeted' it was not going to Dec's to be budgeted (even with a date of today). When I went forward to January, it was adding it to January's to be budgeted which was RED by -450. But none of my other categories previous to January is red. Where is the underfunding coming from? How can I tell?
Negative/red TBB is overbudgeted. This is something you've done via budget entries. You've assigned more money to categories than you actually possess, and funds are consequently double-booked.
Red categories are overspent, meaning a transaction amount exceeded the Available funds in the category. This is a slightly different issue with a different cause; however, the result is similar: funds are also double-booked.
Because you're overbudget, you need to reduce one or more budget entries (possibly below zero, meaning a negative value) until the future TBB is $0. I suggest you pick on the lowest priority category in the future first.
The current and future months are one big pool. There's an unfortunate design flaw existing from launch that doesn't let you see whether you've double-booked funds between the current and future months. Search for "Stealing From The Future" for more details. Apparently, it's bitten yet another user.
As a quick tip, consider keeping TBB at $1 instead of $0. Outside of cash/red overspending, that guarantees the future TBB is also $1.
A TBB of $0 cannot be relied upon to be accurate when Budgeted In Future is nonzero.
It's a mystery why YNAB hasn't implemented even a simple GUI warning when funds are double-booked. The Toolkit Extension (a 3rd party browser add-on) has had this for years. (Doesn't work on the mobile app, unfortunately.)