Translation:Let's make it in four days!
To the best of my knowledge, nothing! In polite (~어요/아요) form, statements, questions, commands and suggestions sound the same. However, one usually adds the honorific particle while giving a command to not sound too rude. Henceforth command 'make' would rather be 만드세요, not 만들어요.
Also note that the 'ㄹ' gets deleted from the end of the verb stem (만들) when directly proceeding the '세' particle