Hello
It is normal that they need time for escalations, and sadly, our cases are considered as critical, because they cant just change the email and password like that (hackers changed all the data and encrypted account probably). They have to gather all the info from your account and transfer it on another xbox/microsoft account they will/already ask(ed) you to create.
It will most likely not be 3 days, but 2 weeks because the gathering data takes a long time.
Also it seems the escalation process is rather unpopular on reddit and other medias for suspending accounts, so make sure to ask for a transfer if it does get suspended. Please contact the xbox support (human not ai) from time to time to check the state of the case. if the case gets suspended, you're gonna have to insist heavily or post on other medias with a bunch of visibility to hope to get the case reopened, if they cannot transfer.