If you're on a schedule & trying to get some dramatic results, I'd first limit it to a cheat MEAL instead of a cheat DAY. I would also make it more like a cal-up and a carb-up instead of a free-for-all feeding frenzy.
When I'm on a cut for a show (but still far enough out that I can afford to enjoy a little), I'll make my cheat meal on a Saturday night if I'm going out w/ friends for dinner or out dancing. The "cheat" part is more about having a few drinks, maybe some bread (like the stuff they give you at steakhouses) w/ a good hunk of steak, maybe some fries, but more likely a baked potato (still prefer them plain). Its not about shit-loading but rather just a refeed w / more variety of food and more cals than you are regularly consuming.
The purpose is two-fold - to introduce more variety, a little garbage food, and a good cal intake if you've been on a restricted diet - both in terms of variety and total cals. What I've found if I am on a very restricted choice of food (e.g. chicken, broccoli, eggs, almonds, potatos and protein mix), I usually get lactose-intolerant and pretty much can't digest anything outside of this list. The reason this can be dangerous for a competitor is like this - one time during a prep, I went w/ my trainer (note WITH my trainer - he said it was ok) to Wendy's and picked up a Greek or Caesar Salad - anyway a chicken & salad that had some grated cheese on it. I was careful to avoid the cheese, but must've eaten some because I immediately got bloated up w/ a miserable stomach ache that took a day to get rid of. If something like this happens on show day, you're done. Your 4-6 months of prep ruined.
And as noted above - a cheat meal is for sanity - it can be hard to keep a boring diet going for weeks on end. It limits your life socially - so having that one "out" to get together w/ friends and not be the annoying person who can't eat or drink anything fun, or just never goes out - trust me - competition dieting can be very hard on your social life - I've lost friends during my preps. And having that one "out" per week also helps to refocus once its over so you can dive into another boring week of chicken & broccoli
If you were doing a keto diet, this would equate to a carb-up. if you want to keep the progress moving w/ your cutter (keto diet or otherwise), instead of shit loading on your cheat day -- two things will help: 1) keep it to a cheat meal (or if it helps - set a time limit like 2 hrs to keep things under control) and 2) use it to up the cals, but keep your food choices still good quality - e.g. a good steak or burger, potato, sushi (one of my favs), maybe some drinks, maybe a dessert.
Here's how you know the diet is working - for your cheat meal you look forward to the flavor of your steak or sushi, and have no desire to eat chocolate.
In my freezer sits two big ass containers of ice cream (homemade vanilla and mint chocolate chip) however, i wont be eating them and they arent even mine 
