I feel that we need a fix cause not all months were created equal, nor are they the same from year to year so there's bound to be activity differences.

I suggest that there be no Tier progress for the first 3-7 days of the month (while continuing to track the progress) then use that data to figure out about what you need to set the tiers at to get them to unlock at x day of the month.
i.e. if in the first 3 days of feb we had 300k lions successfully flirted with you could say the average per day is 100k. Then if you wanted T3 of the shop to open around the 20th of the month you could just set the goal for T3 to be 1 million flirts and work your way down from there.

It would require an admin to check numbers and do math or setting up a bot/etc to do it for you but I feel it would make the tiers feel smoother than what we have going on right now (especially after the January issue)

Other somewhat similar suggestions;
[All] Adjust Tier Difficulty
[ALL] Link Tier Opening to Calendar Dates

If you have any suggestions or disagree with my suggestion feel free to comment, I would love to hear what you think!

My other Suggestions!