Hey mike! Caffeine indeed prevents one from going into deep sleep, but it's not such a good idea to have a coffee before bed. We are programmed in such way that we first go into deeper stages of sleep which are very restorative and extremely important for the body. It may be more appropriate to move your caffeine intake to a wbtb, where you take the time to think about lding, your goals, etc., doing induction practices. That way sleep interference will be less.

Good luck!