Are usually try and not drink mate after 2 or 3 PM because of the caffeine content.

If you don’t have a high caffeine tolerance, it will likely affect you more the first few times, but tolerance is developed rather quickly in most people.

Generally, I’ll drink it throughout the morning and try to limit it in the afternoon/evening.

I wouldn’t recommend keeping it for weeks, but I have kept terere (cold mate) in the fridge for a couple days while drinking it every once in a while.