I’d ensure that you attempt the most recent past exam paper questions. Although the same topic would not be examined again, the style of the question is consistent. Usually you are expected to know the issues in the current standard and why it therefore needs to change. Following this you would be expected to apply the new rules or potential new rules.
When there is a change in an accounting standard it is because the current standard does not meet the definitions in the framework (leases), or is not consistent with US GAAP (provisions or revenue), or it is no longer fit for purpose (impairment of financial assets).