I DM an AL group of four. They agree to create new level 1 characters (they are experienced), but ask me to adjust the combat to give maximum possible XP in an adventure, in case they miss out the non-combat XP reward, so they can advance more quickly.
The easiest to do this is by increasing the number of enemies, especially the less threatening ones, like kobolds, zombies, etc.
I try to search AL DMG and found this part (emphasis mine):
You can also adjust the adventure on the fly, beyond the guidelines given in the adventure, or make other changes as you see fit in order to insure your players have a good time.
AL FAQ (emphasis mine):
Sometimes characters fall behind the adventure’s expected level. In these situations, there are two main methods of supplementing character experience. […]
Random Encounters. You can’t grant players roleplaying experience to make up the deficit; however, they may add random encounters as needed (assuming the adventure provides a list of random encounters). See below for more guidance on random encounters.
[…]
The FAQ states that to give more XP to players, you can only use two methods, one of them is giving random encounter, if the adventure has a list of random of encounter.
This makes me think that adding more enemies (or changing the enemies with more XP ones) for the sole reason of guaranteeing maximum XP for each adventure is not in line with the spirit of AL, and wondering if this is ever within the bounds of AL DM "empowered to alter an encounter".
Is giving more enemies than the guidelines (for very strong) or changing the types, for the reason to guarantee max XP, allowed for an AL DM?
Relevant: What are Adventurers League DMs empowered to do for encounter scaling purposes?
Best Answer
The following paragraph implies you can
So, the anti-exploit limitation we have is the maximum XP for the adventure. In your quote, you mention that the DM is allowed to change the adventure
If they are having a good time fighting lots more monsters and having harder challenges, that's fine.
But that makes the challenges harder, and they should deal with it
The thing is: can they actually beat these harder encounters? Adding more monsters, even Kobolds, means the party will have a harder time. They are asking for it. More XP means harder challenges. What you should not do is play these monsters "taking it easy" or fudging rolls to make it come back to the difficulty it was before. Especially in low levels, harder encounters might mean PCs die or even TPKs - and when they ask for these harder encounters, they should be accepting it.
About the AL "spirit"
You might be wondering if that is cheating. In cheating section, it's stated that
As long as you are making things to be fun and inclusive, enjoying the challenge, it's not against the spirit. If the reasoning is "competitive" ("let's brag that we are higher level than that other party!" - or whatever), then yeah, you are going against AL's spirit.