ECC 6.0 Upgrade - Processing work items from old environment

[Zack P]

Hello,

Upgarding to ECC 6.0 from 4.6C. In the development
box, we found that some workflow templates failed
syntax check due to stricter enforcement of data types
bindings. We fixed these issues in the development
environment.

Question 1) What happens to work items created in 46C
after the upgrade? Should they continue to process in
ECC6.0 without issues?

Question 2) What happens to work items created in 46C
for the WF templates which failed the syntax check in
ECC 6.0 (we have millions) when we go live? I
understand that a workflow instance always refers to
the version of the WF template that it was created in
and not to the latest version. Does that mean that
when we go-live, the work items that exist that were
created in 4.6C would be referring to the older (46C)
version of the workflow templates rather than the
newest version (ECC6.0) where the syntax issue was
fixed. Do they then fail?

Any input into how to fix this potential issue would
be helpful!

Thanks,
Zack