FICA withheld by mistake, should I wait to file my taxes?

Hi,

I'm a PhD student and work for my university. One of the offices where I've worked, mistakenly withheld Social Security and Medicare taxes for about $500. I've requested a refund through my employer, they said it will take approximately 6 months to receive the money, but they haven't been able to answer my question as to whether I should just file my taxes with the W2 they sent me or file for an extension.

 

Does anybody know how I should proceed?

If I do file my taxes now, should I enter "0" in my field 4 and 6 or should I enter the amount I was wrongly withheld even if it is being rectified?