Hi there! Prepare for a wall of text. 
It used to be like this:
Total used to mean overall total, the boards and prizing will be constructed and given out based upon which Clans had the most kills, captures, etc.
This was seen in Clan Operations.
Highest Total used to be for Challenges.
The same concept applies now, but the way it's explained is a little different.
For Clan Challenges, these are usually based off of accolades. If you get the highest total kills in a match, you earn an accolade. To get a badge in Challenges, your Clan members will need to earn a certain amount of accolades, with the XP and badge type getting better as you guys get more throughout the Challenge.
So if the Challenge is for highest total captures, you'd need the most in that match to earn an accolade, which would count towards your progress.
If the Operation was for total captures, any captures you and your Clan earned during the Operation will count towards your total, then your Clan will be ranked alongside other Clans on a leaderboard.
Does that kind of make sense? It looks like highest total and total are used interchangeably now, so just do what the competition instructs, and you'll be helping out your Clan!
Challenge boards update slowly, even on the app. It's best to keep track of that stuff yourself.
For enlistment, there are some issues with Clan enlistment not displaying properly, but it's more likely that your leader enlisted your Clan.
^LM
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