I thought I would never ever write anything again, but...
We had a problem with players being able to 'cheat' the system by placing too many workshops and factories then that was intended, this would become a huge problem when we made the quest endless. So we try to tackle this issue on different ways, last event we tried it with 'complete province' quests
...and you failed.
this time we try it with current advancement quests.
Sadly, you will fail again unless you change a thing or two. Please let me tell you that players were not the problem. Your event mechanics was. You have created a "Perpetuum Mobile"-style mechanics that allowed many players to turn your intended pretend-to-be-endless quest cycle into a really endless one.
There are two possibilities: eighter event testers by IG are average players at best and they hit the wall too soon (in other words: at some point they were not able to jump over the "two provinces" hurdle any more) or some event designers by IG suffer under lack of imagination. Well guess what ? Players don't
Leave the quest line endless and some players will always beat the system, they will always find a way to do it. No matter what what you try, no matter what hurdles you put in their way - you will not succeed as far as some players are concerned, but the "normal" casual players will suffer because of these hurdles.
Therefore, please drop the idea of pretend-to-be-endless-quest-line-which-we-try-to-prevent-to-be-endless-anyway. It does't make any sense and since it's going to fail again, it only will punish the majority of players. Moreover, if this event appears on live in this shape and form you will damage the game balance permanently (at least the tournament balance) or even worse: you will have to fix or "rebalance" few things after the damage had been done. It will be possible to obtain more than one powerful Bear of a kind, are you kidding me ?
Although "possible" is not the right way to describe it. It WILL happen. One Brown Bear is totally OP in my opinion (as the Fire Phoenix was), but allowing players to have more than one is... I don't know, "careless" is a polite way to describe it, especially the Brown Bear is waaaay to powerful to allow that. You think the reduced amount of pet food will make it impossible to "run" more than one Brown Bear on pet food permanently ? Surprise, surprise. Players are already exchanging some ideas how to deal with it and they will succeed (as I mentioned before, they don't suffer under lack of imagination or creativity).
Few suggestions to make my feedback constructive:
1. It would be reasonable to make some quests easier (e.g. by introducing some reasonable additional alternatives as mentioned by other players).
2. but please make it impossible to get more than one Bear of a kind.
3. or add some REALLY hard quests to the late cycle.
4. or reduce the amount of keys for late cycle quests significantly.
5. Last but not least (as a matter of fact, it's the most important point): the randomness of the quests won't stop players from "cheating" the system (as you put it) unless you remove 4x8h time boosters from the 85-chest. They make it possible to "cheat" in the first place. Using the quest- and the chest system wisely makes it possible to complete nearly every single quest using time boosters and never run out of them. The only thing that can stop you is running out of ressources due to a huge number of map conflicts solved. I tried to estimate the average cost (time boosters are meant) of the late cycle quests in the current event. It's not significanty higher than the cost of Mermaids event cycle quests. Conclusion: you are creating a Perpetuum mobile again (being one of those "cheaters" I know exactly what I'm talking about).
6. Please dont't try it with the endless quest line ever again
It's a bad idea and it will always go wrong, one way or another. You will never be able to balance it properly, you will never be able to prevent some players from finding a way to jump over your hurdles and you will always have a great number of unhappy players as a result. Even those "cheaters" aren't as happy as you might think. Winning literally hundrets of main- and daily prizes, thosands of % in portal instants and thousands of hours in time boosters takes the whole challenge out of the game.