Another option might be to add triggers to your tables to capture the changes into "temporary" (not necessarily tempdb) tables. This would resolve the issue of the deletes. ...

select ScenarioID,

dateadd(minute,

(datepart(minute, StartTime) / 30) * 30,

dateadd(hour,

datepart(hour, starttime),

convert(datetime, convert(varchar, StartTime, 1)))),

...

select * from person where exists

(select * from vehicle where vehicle.personid = person.personid and vehicle in (05, 10, 15))

and not exists...