Not true! You can submit some late work and get an A in this class, provided that you only request one extension in the semester and you submit your work by the new agreed deadline.
Please read the contract-grading part of the syllabus carefully to know how final grades are determined.
In this class, you can earn a bonus of half a point on your final grade by doing the extra-credit option (e.g. from B- to B, and so on). This opportunity is to submit an optional take-home exam (please see sections in green font on Syllabus for more info, and you can find the optional exam file under Assignments in the main menu).