Not necessarily.
If you are a hundred percent sure there are no hidden carbs in that bread (run it through the Hidden Carbs Inspector, link to the right here) and your ration is what you say... I know that Nille on this board has some kind of "bread like" thing every morning too. She mailed the people at Atkins.com to check if it was ok, and they gave her thumbs up after checking the nutrition values.

But I suppose it's also a matter of *which* carbs we eat, not only how many - since fast carbs (carbs with a high glycemic index) affects our insulin differently to slow carbs (with a low GI). I.e. high GI food creates blood sugar spikes and falls, which in turn creates cravings and possible bingings.

To be on the safe side, maybe email the staff at atkins.com about it? (It usually takes a while before they answer, though, I guess they have tons of mails in their inboxes.) By the end of the day, it's all got to do with how rigorously you want to follow the A-plan or not.

Best of luck!

/gil