How do I split a string on a delimiter in Bash?

I have this string stored in a variable:

IN="bla@some.com;john@home.com"

Now I would like to split the strings by ; delimiter so that I have:

ADDR1="bla@some.com"
ADDR2="john@home.com"

I don’t necessarily need the ADDR1 and ADDR2 variables. If they are elements of an array that’s even better.

After suggestions from the answers below, I ended up with the following which is what I was after:

#!/usr/bin/env bash

IN="bla@some.com;john@home.com"

mails=$(echo $IN | tr ";" "\n")

for addr in $mails
do
    echo "> [$addr]"
done

Output:

> [bla@some.com]
> [john@home.com]

There was a solution involving setting Internal_field_separator (IFS) to ;. I am not sure what happened with that answer, how do you reset IFS back to default?

RE: IFS solution, I tried this and it works, I keep the old IFS and then restore it:

IN="bla@some.com;john@home.com"

OIFS=$IFS
IFS=';'
mails2=$IN
for x in $mails2
do
    echo "> [$x]"
done

IFS=$OIFS

BTW, when I tried

mails2=($IN)

I only got the first string when printing it in loop, without brackets around $IN it works.