You can view how much is due to be settled on your next paycheck by logging into the app, heading to your Track page, and checking the Pay transfers box. There you will see two figures:
The top figure will tell you how much you have transferred since the beginning of the current pay period. This is for your tracking purposes.
You will then see an amount "due to be deducted from your next payslip" highlighted in blue. This is the total Pay transfers due on your next payday.
You can also check when a Pay transfer is due to be settled by selecting the Pay transfers box, tapping on the Pay transfer, and then scrolling to Settlement details.
If you are on an arrears schedule, you may see your previous Pay transfers carry over and be due in your next paycheck. To check if this is the case for you, you will need to check your Salary Statement to see if any of your previous Pay transfers were split and/or carried over.