PM- HR data transfer in CO1P

Dear Friends,

During a business closure of few orders I got the error message No:CO 688.

Unprocessed future change recs for order xxxxxxx prevent del.
flag/completion
Message no. CO 688
Diagnosis
There are still future change records or error records from the
confirmation for confirmation processes for the order 1866824. Future
change records are possible for the following confirmation processes:
automatic goods receipt
backflushing
calculation of actual costs
data transfer to HR.

So now i run CO1P and it returned me a screen with HR data transfer and then I selected the record and saved it.

Though it took long time this was processed and I was able to close the order then.

We have PM HR integration.

Now my doubt is that:

What exactly it means by HR data transfer??For many other orders why error message CO 688 was not shown.

Apart from CO1P what needs to be done to do "Data Transfer to HR" for a PM order.

Can some body give me some inputs on this?

Regards,

Lekha.