In WordPress 4.7, Posts cannot be filtered based on modified, modified_gmt, date_gmt fields.
Using this plugin we can specify the column(any of date, date_gmt, modified, modified_gmt) as query parameter date_query_column to query against value(s) given in before and/or after query parameters.
Use the date_query_column parameter on any post endpoint such as /wp/v2/posts or /wp/v2/pages in combination with before and/or after parameter.
/wp-json/wp/v2/posts??after=2017-11-08T13:07:09&date_query_column=modified