There was absolutely no price difference between the Cyber Monday Sale and the current subscription price

Because as I mentioned in the first comment, you took that screenshot on an outdated version of Apollo when the sale was over, the Cyber Monday sale was no longer active (you posted this on a Thursday, which is not Cyber Monday).

To explain it once more, I set the prices in US dollars in App Store Connect, Apple then rolls that out to apps in the appropriate currencies, and that displays immediately. Apollo 1.14.13 (or something similar to that) had text about a Cyber Monday sale. When the sale ended, I submitted Apollo 1.14.14, removing the text about a Cyber Monday sale, and updating the price. At this point your version of the app has the non-sale prices (because the Monday sale is over, it's Thursday), but you haven't updated the app, so it's still showing a screen about a sale, because the version you can update to is the version that removes that.

This is akin to viewing a Cyber Monday email on a Thursday and wondering why it still says there's a sale but when you click through to the website, the prices are no longer sales (the email, like the app, is outdated at that point, because Cyber Monday is over).

Your own screenshots literally show there was a sale. It's 59.99 Euros currently, and was 53.99 Euros during the sale.

Please apply just a little bit of critical thinking here. In a community of 3/4 of a million people, do you think I managed to bamboozle every single person (except you!) that there was a sale over Black Friday when I secretly, and evilly kept the prices the same, and you're the first person to discover this? Or is it more likely that rather than a conspiracy, there's a slightly misunderstanding?

What on earth are you talking about? The price is based off the USD price, which was 50 USD, which Apple converts to 59.99 Euros. This was the price before I dropped it on Black Friday (eg: the Thursday before), and I dropped it to 45 USD for Black Friday which Apple converts to 53.99 Euros. Here is a literal screenshot of what it looks like in App Store Connect for Apollo.

I don't know where you're getting 66.99 Euros, that's not even a valid price that can be configured on the App Store, as it's right between Tier 51 and 52, so I cannot set Apollo to that. There is no Tier 51.5. Again, here is a screenshot.

If it was that at one point, it was because at a past point Apple converted USD to Euros differently, but at this point (December 5th, 2022) this is how Apple converts the prices. I have no control over the conversion, I simply set the "Tier", (which is basically just USD until you get over Tier 50), and Apple controls the rest. In your country Apple recently tweaked the Euro conversion rate, which took effect when I changed sales prices in USD. But I have no control over the conversion rate.

Again, if you can't be bothered to read the above, the short of it is that I set the price in USD. That's all I get to do. Apple handles the rest of the pricing for the rest of the world based off of this. The price went 50 -> 45 -> 50.

Please take the tinfoil hat off, not everything out there is a conspiracy.

Photo was taken Saturday 06:49 Berlin time.

The first one? Yes, that's why it shows a sale! Saturday is between Friday and Monday, so the sale was active! In the second one, the sale is no longer active, thus the higher price which matches the current price!

I've tried to explain this multiple times, and at this point I give up. Please re-read the existing explanations if they don't make sense, I truly don't believe this is very complicated.