Hello Danny,
Reverting the snap shot will not take much time however when you say alerts, the alerts will be be generated if any violation, during the snap shot revert it may not, hence suggest to perform the activity during a maintenance window.
Regarding copying the config, you cannot copy the config from lower version to higher(version should be same), you need to re-configure it one by one.
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Syed Noor Fazal
Product Support Engineer
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