bkeiller our good man, this has happened to all of us I believe. First, I doubt any sportsbook, agent or local guy is going to give you the boot if you have been donating to them. Second, you were not trying to hammer multiple max limits. It's a sticky wicket no matter how you slice it.
I usually find key injuries or issues before the sportsbooks with teams or players or golfers etc., and I've bet them and I'll estimate I've had 55% cancelled. The sportsbooks simply took the game or matchup off the board and cancelled my wager. Why?!!!!!!! Because we beat them to the punch. They cannot stand to be outsmarted so their recourse is to void your ticket. Is that moral?
In your case it is different. The difference between +150 and/or -150 is an input error, I don't have a problem with them cancelling that one. I've gotten a few through the cracks and I'm not feeling guilty one bit.