The term "Accrued Weeks" is just another way of describing Banked Weeks. These are weeks that have been allotted to timeshare owners based on their programs, but, for whatever reason, were never used. These unused weeks accrue and can be used later. For example, if a timeshare program afforded one week per year, and the owner hadn't used their timeshare in three years, they could choose to spend three weeks in their timeshare in one year.
Accrued or banked weeks are just another way that timesharing is more flexible than other vacation options. Even if you aren't able to use your property for a week, you won't end up paying for unused time. And saving up weeks is a great way to ensure a longer vacation, should you really want to immerse yourself in the particular culture, or relaxation opportunities provided by your favorite vacation destination.
Accrued weeks may also be exchanged for weeks at another resort within a particular network; whether its your resort's specific family of resorts, or your exchange company's available properties. Not all timeshares programs offer this privilege, and usage is based on availability. If you'd like to ensure that your unused weeks will accrue, check with your specific resort before you buy timeshare there.