Creating Index for array fields with dates in

SQL++
2 
CREATE INDEX ix1 ON ticketingsystem(DISTINCT ARRAY entry.dt FOR entry IN ticketstatustimestamps END) WHERE `$_meta`.mandant = "bt" AND `tickettype` != "Monitoring" AND `ticketnumbertext` != "";


SELECT  t.ticketnumber, t.ticketstatustimestamps
FROM ticketingsystem  AS t USE INDEX(ix1)
WHERE t.`$_meta`.mandant = "bt"
       AND t.form = "frmTicket" AND t.`tickettype` != "Monitoring" AND t.`ticketnumbertext` != ""
       AND  ANY entry IN t.ticketstatustimestamps
            SATISFIES entry.status IN ["05" , "10"]  AND entry.dt BETWEEN "2020-09-29" AND "2020-09-30" END;

OR

SELECT  t.ticketnumber, entry
FROM ticketingsystem  AS t USE INDEX (ix1)
UNNEST t.ticketstatustimestamps AS entry
WHERE t.`$_meta`.mandant = "bt"
       AND t.form = "frmTicket" AND t.`tickettype` != "Monitoring" AND t.`ticketnumbertext` != ""
       AND entry.status IN ["05" , "10"]  AND entry.dt BETWEEN "2020-09-29" AND "2020-09-30";

https://index-advisor.couchbase.com/indexadvisor/#1

Also checkout strategy followed here Array indexing with multiple parameters selecting support