Maybe Adam Corolla will be in "the chair" instead of Artie. Would send a message.
Adam will be at home doing his first "homemade" podcast, he won't be in Artie's chair. For that matter, Adam will never be taking over for Artie Lange on the Howard Stern Show. I don't see that happening.
If Howard were truly interested in sending a message to Artie, he would advise Artie to take a couple of months off to visit a real rehabilitation center. Howard has explained numerous times that he's not Artie's protector or father and that Artie is a big boy and should be able to deal with his own life on his own terms. At best Howard could only truly advise Artie on what he thinks is best for Artie.
I think throwing any comedian into Artie's chair as a way of sending a message is a risky and largely uncommunicative way of getting your point across, especially to someone that appears to be unable to not only hear the advice of others, but to hear the advice and to apply it to one's own life.
Adam will be at home discussing red turn arrows and horribly stupid radio program directors, such as the one he has worked for and derided on the air for the past three years. The Artie chair will either be empty of the three hundred pounds it is used to carrying or it will be pressed a few inches closer to the floor should Artie show up, either way it will be business as usual for the Stern Show.