Dynamically emailing users tagged in Notes Field

I'm trying to dynamically target users when they've been mentioned with an '@' symbol in the Notes Field. So far I am able to pull the names into a Formula List Users field and email them. But I don't want to email every name that's ever been mentioned. Just the mentions in the current Note's entry.

So, is there a way to clear the Formula List User field, add any user in the newest Notes entry, and just email that person?

// Make list of all @callouts
var text CalloutList =
List(";",
Left(Part([Task Notes], 2, "@"), " "),
Left(Part([Task Notes], 3, "@"), " "),
Left(Part([Task Notes], 4, "@"), " ")
);

//Parse each call out
var text calloutOne = Part(ToText($calloutlist), 1, ";");
var text calloutTwo = Part(ToText($calloutlist), 2, ";");
var text calloutThree = Part(ToText($calloutlist), 3, ";");

//Convert callout name to an email
var text calloutemailone = Case($calloutone,
"lee", "lgilmore@quickbase.com",
"kris", "kkeene@quickbase.com",
"adrian", "alloyd@quickbase.com");
var text calloutemailtwo = Case($callouttwo,
"lee", "lgilmore@quickbase.com",
"kris", "kkeene@quickbase.com",
"adrian", "alloyd@quickbase.com");
var text calloutemailthree = Case($calloutthree,
"lee", "lgilmore@quickbase.com",
"kris", "kkeene@quickbase.com",
"adrian", "alloyd@quickbase.com");

//Display list of callouts
//ToUser($calloutemailone & "; " & $calloutemailtwo & "; " & $calloutemailthree)
 
ToUserList(ToUser($calloutemailone),ToUser($calloutemailtwo),ToUser($calloutemailthree))​

​​

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Alexandria
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