How long does it last in fridge?

I have never had it last longer than a couple of days.

It should be fine in the fridge for up to 1 week. After that, I think the flavor will not be as good.

While it might actually last for over a week in the fridge, I would expect it to lose some of its fresh flavor after three days since it contains a number of fresh ingredients (lemon zest, butter, fresh thyme, and lemon juice).

I would freeze any portion that isn't intended to be consumed in three days.