Okay, so here's the thing: If you go low carb, your body gets used to it. Your blood glucose normalises, possible damage that was slowly developing may start to heal. That's all really nice, I can tell you!
And then there are cheat days. And there is no way to tell how you'll respond to those. There's a few things that can happen though.
Carbs are addictive. They stimulate the pleasure center (no wonder you are mourning your favourite foods, right?), and like any addiction, for a lot of us, you can't just have a little. I know very well that after not having smoked for 16 years now, if I light one up, I'll be lighting one butt with another by the end of the day. Same with carbs. Put more carbs in, you'll likely crave more carbs. Pringles don't say "Once you pop, you can't stop" just for the heck of it. Who ever stopped at ONE Pringle? That's a risk right there. After a load of carbs you can possibly experience withdrawal symptoms all over again when you get back on the wagon the next day. Headaches, irritability, massive hunger and cravings that are just hell to deal with, putting you back to square one. And that's if you go right to cold turkey. Some can't and just have a little bit of carbs, and another bit, and another little, because how much can it hurt? Carb creep, it happens. Before you know it you're back to your old diet. That's risk number two. And neither of those might happen, for all we know.... You might spike a bit after a meal, and go for a walk to burn it right off, and not feel any ill effects. If I eat something carby I feel confused, my legs get rubbery and my heart starts racing: I don't handle steep rises well. Might not happen to you though. That's the thing.
You won't know which of the above is true for you, until you live through it, and use your meter to see what happens.
A lot of us relax our diet some around the holidays or a special event like a wedding. And a few months later a few members who've gone very quiet for bit around Christmas, come back in saying they fell off the wagon and need to get serious again. Carb creep. We know it exists, but sooner or later, quite a few of us will fall prey to it. Because you know what? We're human. And we do get to start over if we slide down a slippery slope. And T2 is an individual thing, how you handle it is completely up to you (It IS your body after all, you have to live in it), so yeah.... Pick a route that is workable for you. Because no diet is going to work if you feel like it is keeping you prisoner. Find things you love having on your plate, and you'll get through this. With or without cheat days.
Good luck eh!
Jo