Switching from Tire-4 to Tire-2 visa

Hi Everyone,

Myself Aravind, I'm currently doing master's in UK staying on Tire-4 student visa and my Visa is going to expire on May 17th 2020. I got the job in UK and they are ready to sponsor me Tire-2 visa. But, my University said they will release my results in June 23rd 2020(by the time my Visa will expire). To apply for tire 2 visa, I have seen in the UK home office website saying that I don't the master's certificate. If I have a letter form University saying that "his course will complete in 40 days" is enough for visa application is that correct? If that is correct how it will work any ideas? please share with me.

Thank you,
Aravind