What's going on with SFDC Type?

I need some help pretty please!

The SFDC Type field (the Person one that is) seems to have changed.

The available values in the list are now:

- Contact

- User

- Person

In other words there is no longer a value for "Lead".

I am trying to trigger on Data Value Changes and it's not firing off and I can't help but think this is causing my issue.

When I look at my test record the literal value in the SFDC Type field is "Lead" but this is not an optional value in the trigger?

I am trying to trigger on a Lead Conversion. All the documentation is so out of date!!!!

There is no "field" called "SFDC Is Converted" either!!! However there is a "trigger" called "Person is Converted.

Can anyone shed some light on this mystery for me pretty please?

Given that the actual record says the value in the field is "Lead" should I be using that in the trigger? Or some "Person" somehow magically map to "Lead" despite there being no documentation on this?

Thanks in advance everyone.

Cheers,
Sean