If your album campaign has singles released before the main album release date, you can make those tracks available to preview and purchase.
Tracks that are available to buy before album release will also be made available for customers to download if they have purchased the whole album. This is known as instant grat.
How to set up instant grat.
Track > Actions > Enable Pre-order Purchase / Download
You will also need to Enable Pre-order Previews.
You can also set this for multiple tracks at once by bulk selecting tracks on the product page.
Product > Multi-select > Edit Selected > Enable Pre-order Purchase / Download
You can have multiple or all tracks on an album previewing, but only one or two instant grat. tracks, just select as you wish.
Preview lengths can be set per product and track if your campaign requires it. Otherwise they will default to your "Store Settings".
Making tracks available for download before release date shouldn't affect chart submission as long as your UPCs are registered with the relevant charts company and adhere to their track pre-order eligibility rules. If in doubt, please contact the requisite charts company.