You used to be able to hit botd during a life window and you would be reverted back to botd state but they changed that because apparently too many people were hitting it by accident.
Now for drgoons you want to do delayed life on most fights, which is entering your first life window at around 1:1x into the fight instead of 0:4x so 2/3 of your nastronds can catch the b4b and trick attack buff and you also set yourself up to catch most other raid buffs during your life window for the rest of the fight.
For delayed life, you would usually have your 3rd nastrond and the 1st nastrond of your next life window be under b4b buff, which means you would be doing a "double life". This means entering life of the dragoon back to back as soon as geirskogul is off cooldown. However, if your gcd falls between a certain range (I forgot but you'll know when it happens to you), you wouldn't be able to pull this off since your 4th and 5th hit, which extends your botd timer, would go off right before you exit the life window and you almost never want to enter a life window with less than ~23s left on your timer since you wouldn't have enough time to use 3 nastronds that way.
Since geirskogul and jump has the exact same cooldown, you also wouldn't want to keep the difference on their cd for more than 3-5s away from each other since you'd be entering suboptimal life windows that way and you'd also lose out on a lot of usage of geirskoguls in the process. Your life window is effectively useless once you have fired off 3 nastronds. So if I were allowed to exit that window any time I want by pressing the botd button say, right before my 4th or 5th hit, I would have enough timer to enter another life window right away without having to worry about forcing a clip due to having too little time on the timer or straight up not having enough time to use a third nastrond.