3442890 - Query with cast function is not returning expected results - SAP IQ

• A query that had been working suddenly stopped returning results.  The html is creating many plans with no data.
  SELECT CAST(CASE WHEN EXISTS(SELECT * FROM tclient cl JOIN tclient2 map ON cl.fid = map.fid WHERE cl.fcode = 'INFO' AND map.fsid = 3) THEN 1 ELSE 0 END AS BIT) as available   
• This is preventing reports that were previously created in seconds, to not being created at all.
• No errors in the IQMSG nor the SRVLOG.
• Would like to know why this is failing.

SAP IQ 16.1

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