UPDATE `###_users`
SET params = CONCAT(
'{"admin_language":"","language":"","editor":"","helpsite":"","timezone":"',
CASE
  CONVERT(IF( SUBSTRING_INDEX(SUBSTRING(params, LOCATE('timezone=', params)+9 ), '\n', 1) = 0, '999', SUBSTRING_INDEX(SUBSTRING(params, LOCATE('timezone=', params)+9 ), '\n', 1)), SIGNED INTEGER)
WHEN -12 THEN 'America/Adak'
WHEN -11 THEN 'Pacific/Rarotonga'
WHEN -10 THEN 'Pacific/Honolulu'
WHEN -9 THEN 'America/Anchorage'
WHEN -8 THEN 'America/Los_Angeles'
WHEN -7 THEN 'America/Phoenix'
WHEN -6 THEN 'America/Chicago'
WHEN -5 THEN 'America/New_York'
WHEN -4 THEN 'America/Santiago'
WHEN -3 THEN 'America/Sao_Paulo'
WHEN -2 THEN 'Atlantic/South_Georgia'
WHEN -1 THEN 'Atlantic/Cape_Verde'
WHEN 0 THEN 'Europe/London'
WHEN 1 THEN 'Europe/Zurich'
WHEN 2 THEN 'Europe/Athens'
WHEN 3 THEN 'Europe/Moscow'
WHEN 4 THEN 'Asia/Dubai'
WHEN 5 THEN 'Asia/Karachi'
WHEN 6 THEN 'Asia/Dhaka'
WHEN 7 THEN 'Asia/Jakarta'
WHEN 8 THEN 'Asia/Singapore'
WHEN 9  THEN 'Asia/Tokyo'
WHEN 10 THEN 'Australia/Sydney'
WHEN 11 THEN 'Pacific/Noumea'
WHEN 12 THEN 'Pacific/Auckland'
ELSE ''
END
,
'"}');