Will overstaying my visa for 6 days after the amnesty period create major issues at the airport?

Before you do that...

Go to your Thai Immigration office...

Apply for a 30 day extension...

If denied you may be given 7 days to leave Thailand.

Cost of this is 1,900 Thai baht.

Cost of 6 days overtstay is 3,000 Thai baht. ...(6x500 day fine)

Do this on Friday of this week

As the denied 7 days start the day of application.

If you already have a booked flight departing Thailand..

Take a copy of your airline ticket

with you to show the immigration officer.