I didn't look at this in detail but I noticed this:
```
AND
a.InsertDate = f.pl_insert
AND
b.InsertDate = f.pe_insert
AND
a.ProjID = f.projid
```
As long as you mention those in the WHERE clause it won't be a real left join. All constraints on F must be in the ON clause.
Now if you really want to filter away rows in A using those booleans that's fine. That's legal and often reasonable but at that point it isn't really a LEFT JOIN anymore. You're effectively inner joining from A to F over projid.