this is what I've learned about the daily quests. it is possible to complete the quest while you are in a lower league and than grind to higher league to claim a bigger reward. also if you don't claim the reward for a number of days, you are not going to receive several quests in one day after that. daily quests do not accumulate.
by the end of last season I had a reward to claim in gold III. so I wanted to rank up to gold II and open more cards. but I accidentally missed the end of season. that was unfortunate 😂
ps. got my second golden card!