I do not know about Tradebullet. But if you are using Tradestation to give Tradebullet the commands for exit at end of day you have two options. You can add a start and end time to the code and it will exit at the end of the bar after the time you set. For example, if you are using a 3 minute bar, it would exit 3 min before the close. The second option is to make a custom session time and use SetExitOnClose in code. It will exit at whatever time your session ends. You can make that one exit 1 min before end of day. If you really want to exit at the very end of the day it has to be done with a Limit Order but that is a bit more complicated.