Is the engram reward power-level determined upon receiving, or decrypting?

I recently hit max level in Destiny 2 and have started my path on gearing up to do raids. I have a general idea of how gear level is determined, slightly above your current, so that you steadily increase in power.

I have noticed that when I get an engram, the power level of the items inside are sometimes lower than my current power level. If I want to maximize the power level of each engram that I open, would it be best to wait until my power level is as high as possible?

Or is the power level for the engram rewards determined when you get the engram?

Solution 1:

It depends on the type of engram.

If you are killing enemies in the wild and a legendary engram drops, the power level of that engram is determined when it dropped. Once you pick up the engram, you can see what power level it will be by hovering over it in your inventory screen.

On the other hand, powerful engrams determine their power level when you pick them up. You can get powerful engrams from completing weekly milestones, clan rewards (picked up from Hawthorn in the tower), and loot from raids.

Solution 2:

After looking on reddit I did a bit of research and probably should have checked the wiki first (even though it is not a perfect source)

From the wiki on engrams.

Each engram is of a particular weapon or armor type and stored in the Guardian's corresponding inventory slot until decoded. When decoded, engrams become a particular weapon or armor piece, scaling with the player's level at the time it is decoded. Engrams can sometimes decoded into a different type of item, such as a Strange Coin or Artifact.

Emphasis mine.

It appears it is when it is decoded, not when it is looted.