How do I check which adjustments still need reversing?

Any adjustment requiring reversal has a 'Reversal' (two-way arrow) button to the right-hand side. You can review these within the Creditor and Debtors table, selecting the type of creditor or debtor from the drop-down menu.

If you're using the detailed dashboard view (as opposed to the flow view) set in System Settings, the number of outstanding adjustments is recorded in the Overview tab.