If that were the case, you would be stage-ready shredded at ~240-245#. To put that in perspective, Arnold was ~6'2", and competed at ~230-235#. So unless you are an absolute tank--we're talking bench/squat/DL in the 500/600/700 neighborhood, and a massively muscled individual--I'm afraid you are not carrying anywhere near 230# of LBM. In fact, at 5'10", if you are carrying 'just' 180# of LBM (which would translate to a shredded stage weight of ~190#), that would be very impressive.
To give you a sense of the sort of physique I'm talking about, have a look at @bulldog9899's log. I don't know how tall he is, or how much he weighs, but he's a huge strong guy. If you are 18% BF at 280#, your physique will be akin to his--massive and very 'solid looking.'
I'm not trying to discourage you; I just want to give you a more realistic impression of what you're dealing with, and of what's in store for you vis a vis the body composition changes you can expect as you lose weight. (I know from personal experience how disappointing it is to hit a BW goal, only to find your physique looks nothing like what you expected it to at that weight.) Best of luck reaching your goals.