Also when I make the application I will not have the flight details or exact date - will this be a problem.

Dear Ms Samantha Sor, Thanks for your question in our website. We are pleased to answer your question. If you want to enter Vietnam in this week. So please apply Visa Online today via our website today. Link to apply: https://www.vietnam-evisa.org/apply_visa At least in 2 working days, we will send to you approval letter. Therefore your visa is ready for you. In normal case you don't need to send us the exact flight number and arrival date. You can enter Vietnam whenever you want in valid visa time. We only need Flight details and arrival date in emergency case. If you have any questions, please feel free to contact us. Best Regards,