Try this:
IF(
IS_AFTER(
DATEADD({Date Registered}, 90, 'days'),
DATETIME_PARSE(
'01062024',
'DDMMYYYY'
)
),
DATETIME_PARSE(
'01062024',
'DDMMYYYY'
),
DATEADD({Date Registered}, 90, 'days')
)
Do note that the year for 1st June is hardcoded though. We could make it take the current year into account, but that would mean that the previous year's records would be all weird you know what I mean?