If sportingbet discover or suspect you use arbitrage they will suspend your account and void all bets on the account, including retroactively voiding previously won bets.
All other honest bookies behave in a different fashion, simply preventing further bets but honouring all earlier bets.
Sporting bet voided bets and thus confiscated over 3000 pounds of funds in an account. My advice would be never to trust them unless they reverse this policy and, like other bookies, honour previous bets placed even if they no longer want you as a customer.
Sporting bet terms and conditions quoted below.
1.4 The Sportingbet site and the promotions offered to Sportingbet customers are designed for customers taking part in recreational betting and gaming and if we believe that the bets are being placed or the site is being used for any other reason, other than recreational betting, for example but not limited to fraud, collusion, arbitrage or matched betting, then Sportingbet reserves the right to refuse or void bets, to refuse to grant a bonus or promotion, to exclude a customer from Sportingbet bonuses, rewards or promotions on an ongoing basis or to close a customer account without notice. Sportingbet undertakes customer profiling in making this determination.