From this page https://docs.atlas.mongodb.com/bi-connection/ it appears that the BI Connector for Atlas is available if I have an M10 or larger cluster. I upgraded to an M10 cluster to get the BI connector only to discover that if I enable the BI connector, it charges me additional costs. I could not find these additional BI connector prices detailed anywhere on your website except for in my account after I upgraded to the M10 cluster. And even these pricing details are not clear:

BI Connector
$1.47/day for sustained monthly usage
pricing for M10
or $3.84/day, up to $45.00/month maximum

What is sustained monthly usage? When does the $1.47 rate apply vs the $3.84 rate? This is very confusing. Please detail these costs somewhere on the website so I can understand them before I purchase an M10 cluster. Thanks!