Date filter last 3 months

or try this

= Table.SelectRows(#"Expanded std_case_service_file_individuals", each [event_start_timestamp] >= Date.AddMonths( Date.From(DateTime.LocalNow()),-3))

Hi cb_wcc ,
You can try this 

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("XdMxjsMwEEPRu6RewB5KNO2zBLn/NRbbLPhTstLHPOj9fu1jDp3ar8/P31CP1WP3cI+rR3rcPZ4ec2KhYRAxqBhkDDoGIYOSQcqgRWgR74EWoUVoEVqEFqFFaBFaVrW4adw0bho3jZvGTeOmcdO4aQwag8agMWgMGoPGoDFoDBqDxqAxaAwag8agMWgMGoPGoDFo/EWzquU6MNRj9dg93OPqkR53jwePnlgMQsSgYpAx6BiEDEoGKYMWoUW8B1qEFqFFaBFahBahRWhpqDRNmiZNk6ZJ06Rp0jRpmjRNQBPQBDQBTUAT0AQ0AU1AE9AENAFNQBPQBDQBTUAT0AQ0AU2+aPoP3QeGeqweu4d7XD3S4+7x4NETi0GIGFQMMgYdg5BBySBl0CK0iPdAi9AitAgtQovQIrQILQstDfUcGOqxeuwe7nH1SI+7x4NHTywGIWJQMcgYdAxC/qE+vw==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Date = _t]),
    FilteredRows = Table.SelectRows(Source, each Date.From([Date]) > Date.AddMonths(Date.From(DateTime.LocalNow()), -3))
in
    FilteredRows

Final output

Best regards,
Albert He

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