So I've just entered Jool's SOI for the first time ever, and as I was attempting a gravity assisted brake maneuver, I ended up stuck in "acceleration mode" where I could no longer time warp or return to KSC for several long minutes. What causes me to remain in acceleration mode while my engines were off? Is this normal? It was only after I left the room to do some chores and returned did I finally regain time warp, but even then, the acceleration mode flickered as I did so.