If you click on "Companies" in the left nav, then click on one of the businesses you have setup in TPP, you will find several options for how you sync to your bookkeeping software.
Besides changing the software you sync to, you can also manually sync to your books with the "Sync Now" button (if you changed something in your bookkeeping and want to reflect it in the projections) and you can change the settings for your projection data.
This relates to how often you want TPP to update the projections from your business bookkeeping software.
Linear- Uses the data from Jan 1 of the current year until today, then extrapolates what the rest of the year will be.
Rolling Average- Uses data from the last 365 days each time it syncs.
Last Year- Uses the prior calendar year of data.
Choose between accrual or cash basis depending on what your tax return uses. Most taxpayers are cash basis.