HTTP Certificate Expiry Date location

Whenever we renew our cert, I set an Outlook reminder a month in advance of its expiration date.

I found a PowerShell solution to check this for a farm of servers. (I lightly modified it.)

https://stackoverflow.com/questions/39253055/powershell-script-to-get-certificate-expiry-for-a-website-remotely-for-multiple

$minimumCertAgeDays = 30
$timeoutMilliseconds = 10000
# $urls = get-content .\check-urls.txt
$urls = @()
$urls += 'https://docs.ifs.com/techdocs/'
$urls += 'https://www.ifs.com/us/'
$urls += 'https://community.ifs.com/'

#disabling the cert validation check. This is what makes this whole thing work with invalid certs...
[Net.ServicePointManager]::ServerCertificateValidationCallback = {$true}

ForEach ($url in $urls)
{
    Write-Host "Checking $url" -f Green
    $req = [Net.HttpWebRequest]::Create($url)
    $req.Timeout = $timeoutMilliseconds
    $req.AllowAutoRedirect = $false
    try {
        $req.GetResponse() | Out-Null
    } Catch {
        Write-Host "Exception While checking URL $url`: $_ " -f Red
    }
    $certExpiresOnString = $req.ServicePoint.Certificate.GetExpirationDateString()
    #Write-Host "Certificate expires on (string): $certExpiresOnString"
    [DateTime] $expiration = [System.DateTime]::Parse($req.ServicePoint.Certificate.GetExpirationDateString())
    #Write-Host "Certificate expires on (datetime): $expiration"
    [Int] $certExpiresIn = ($expiration - $(get-date)).Days
    $certName = $req.ServicePoint.Certificate.GetName()
    $certPublicKeyString = $req.ServicePoint.Certificate.GetPublicKeyString()
    $certSerialNumber = $req.ServicePoint.Certificate.GetSerialNumberString()
    $certThumbprint = $req.ServicePoint.Certificate.GetCertHashString()
    $certEffectiveDate = $req.ServicePoint.Certificate.GetEffectiveDateString()
    $certIssuer = $req.ServicePoint.Certificate.GetIssuerName()
    If ($certExpiresIn -gt $minimumCertAgeDays)
    {
        Write-Host "Cert for site $url expires in $certExpiresIn days [on $expiration]" -f Green
    }
    Else
    {
        Write-Host "WARNING: Cert for site $url expires in $certExpiresIn days [on $expiration]" -f Red
        Write-Host "Threshold is $minimumCertAgeDays days. Check details:`nCert name: $certName" -f Red
        Write-Host "Cert public key: $certPublicKeyString" -f Red
        Write-Host "Cert serial number: $certSerialNumber`nCert thumbprint: $certThumbprint`nCert effective date: $certEffectiveDate`nCert issuer: $certIssuer" -f Red
    }
    Write-Host
    Remove-Variable req
    Remove-Variable expiration
    Remove-Variable certExpiresIn
}