How do I manage my internship and MBA admission?

MBA admissions are based on graduation. So, you will have to first complete your graduation and then seek admissions. In case, there is an overlap for a couple of months then many institutes give provisional admission too. You can check with the respective institute and then take a call.

Look, one must focus on one thing at one time and while you are doing graduation along with internship, so it is advisable that you must complete the ongoing thing. Regarding extension, you can always call them or just mail them regarding your query I hope they may consider it.