--if you're supplementing with 1000mcg per day of B12 consistently, I'm not surprised that your B12 level is at that number; that just means you're putting a good deal of B12 into your system, where hopefully it can be utilized.

Under those circumstances, I don't think that level is too high. I've had blood draws with much higher B12 levels--one time 1864, believe it or not. I have to explain to the doctors that I supplement consistently.