almost 3 years ago - Destiny Dev Team - Direct link
We’ve noticed some confusion around Seasonal Challenge XP payouts this Season and wanted to clear up some miscommunications on our part. 

First, there was a bug last Season where players who had earned XP bonuses from Season 12’s Season Pass did not have these bonuses reset at the start of Season 13. This carry-over resulted in Season 13 Challenges paying out much greater XP than intended. Rather than opt to fix the bug midseason, we decided to leave it in place and let players continue to benefit from it. We mistakenly did not acknowledge this bug during Season 13, and we missed it in the 3.2.0 patch notes for Season 14. 
The change we did call out in the 3.2.0 patch notes was the addition of a new XP payout size for Seasonal Challenges, called “Extra Large XP.” This payout is comparable to the amount of XP needed to earn half a Season Pass rank with a "Well-Rested" XP bonus.  
With the addition of these Extra Large XP payouts, we also changed the overall naming convention. The reason we moved to this new naming convention was to better highlight that the XP payouts from challenges were larger than from other bounties and activities that show XP as a reward. We did not clearly explain this change, nor was the new naming convention easy to understand. These name changes led to confusion as players began tackling their Week 1 challenges. We understand and agree that the Season 14 name changes are confusing, and the team is looking to update the names for clarity in a future patch. For the time being, here is a quick look at how Seasonal Challenge XP payouts have been updated. 
Season 13 Season 14 Base Payout Size Base Payout Size
(Well-Rested)

Extra Large XP 0.25 Ranks 0.5 Ranks
XP X2 Extra Large XP 0.5 Ranks 1.0 Ranks
Double XP X4 Extra Large XP 1.0 Ranks 2.0 Ranks
4x XP X8 Extra Large XP 2.0 Ranks 4.0 Ranks

[EDITOR’S NOTE 5/21/21 – For clarity, we have added a new column to the above table to differentiate between base payout size (when no additional XP bonuses are in place) and payout sizes with the “Well-Rested” XP bonus. Additional XP buffs can also cause further increases in XP payouts.] 

Seasonal Challenges are still your go-to resource for consistent XP.  Players who complete all Seasonal Challenges and make use of the “Well-Rested” bonus will still exceed level 100 in the Season Pass. We know XP in Destiny 2 can be confusing - sometimes to the point that we miss things ourselves.
We apologize for the confusion with these changes. All in all, between the shifts to the Seasonal Challenge XP payouts and the XP bonus bug fix, we expect players to earn XP and progress through the Season Pass at a similar rate as they did in Season 12. We will keep an eye on the data and your feedback and let you know if we need to make any changes this Season or in Season 15.