If Aubameyang isn't a crucial player for Chelsea, Chelsea management won't force them to sign Aubameyang on the last day of the transfer window. If you followed the issue on Chelsea squad, you must know that Chelsea was looking for a strong CF to be the replacement for Lukaku. Chelsea needs a pure CF to score more goals, Aubameyang is a perfect player to solve the crisis in Chelsea attacking line. Anyway, Havertz isn't a pure CF, so he has nothing to do with Aubameyang's position. Don't you understand that Havertz is an attacking midfielder? 
Honestly, I think Aubameyang is a good player on the pitch. Maybe off pitch he has had some issues. I am quite sure he will deliver for Chelsea on the pitch. He is the kind of guy who can fit anywhere, but sort of unlucky not to settle. Look at what happened in Barca last season. He literally saved them from the embarrassment, only for them to push him out.For me Aubameyang is a great player, that's why he is wanted by a big club. Even though his form declined in his two seasons with Arsenal,
but that was not the reason Arsenal let Aubameyang leave. In the end Aubameyang can prove he is not finished as a striker, Aubameyang played well
with Barcelona last season. That's why Chelsea really want to sign Aubameyang before the transfer window closes. So I believe Aubameyang will make
a big contribution to Chelsea, moreover Chelsea also bought Aubameyang not at a high price. Even if Aubameyang plays badly, it won't be so painful
for Chelsea, unlike when Chelsea bought Lukaku for a very high price. We will see how Aubameyang performs with Chelsea, especially since Chelsea
really need Aubameyang's presence as a striker. Because so far there are not many choices for Chelsea on the front lines, therefore Chelsea often
makes Havertz or Mason Mount as false nines. But with the presence of Sterling and Aubameyang as new players, Chelsea have a pretty strong
front line right now.