We are offered to play a match.

Actually, there are no weeks of high-level monsters; there are weeks of doubled populations of low-level monsters. And a +5 to the population of level 7 monsters can only happen at the end of the month, meaning it can only affect the 5th week. However, overall, I agree that this extra spawn should be banned.

Well... I would argue with that... On the second week, there can easily be a week of level 7 monsters! Once, while playing offline, I just kept trying to generate a week of Spectral Dragons, and I eventually succeeded, although I don't remember how many attempts it took! So, the probability that a week of level 7 monsters will occur on the second or third week is extremely low, and even more so that it will coincide with one of the players – that's pure fantasy... Personally, I've only been that lucky once, and it was a long time ago, and it was with computer opponents... However, the 131st week of the Devil for Inferno pleased me!! :D

And at the end of the month, a doubling can happen!!! But the doubling only applies to a specific type of creature, and they appear on the map, namely:
Level 4 - Pegasus
Level 3 - Griffin, Serpent, Ghost
Level 2 - Gogs, Harpies, Lizards, Wolves
Level 1 - it doesn't matter... or rather, I don't remember :)

P.S.: If you're going to ban the week of monsters, then ban the plague too! Although reloading doesn't always help...