Moving from Tech to a manager role - Can I retain my priority date?

[sumsriva]

I have my labor and I-140 approved through the current job (EB2) - Its a Technical role. I am getting an offer to move on a Management role in the same company. Since my job function is changing, I guess I'll have to re-file for my Labor and I 140(is that a correct assumption?).

In this scenario, will I be able to retain my filing date (through previous application) or do I get a new filing date?
I would lose few years, since my current priority date is Aug 2010.

Please help.