"Corrected" W-2s?

I picked up a new client a couple months ago, with 50 employees, who has handled all the payroll on their own in Quickbooks desktop for the past three years.
He produced 2015 W-2s at year end, gave them to employees..... but did not file with Soc Sec Admin.
Now we review the Quickbooks file, find there are a month and a half of missing pay periods ("oh, my computer crashed, so I had to run those pay periods on a different computer....")
We've amended the 941s and 940.
But.... what about the W-2s? Do I file "corrected" W-3/W-2s with the Soc Sec Admin, or just regular old W-3/W-2s?
The reason I ask is the Soc Sec Admin has never seen W-2s. But employees got them, and obviously filed them with their tax returns so the IRS has some records.
Would you file "Corrected" W-2s.... or just file (regular) W-2s using the now corrected amounts?

W-2s go to three places: IRS, SSA, and employees. If the amounts have changed and they've not been filed with only SSA of those three, I would file corrected W-2s with all three. If only employees received the originals, I would not file corrected, but include a letter to the employees when the updated forms are delivered.

Captain, thanks much. But I'm confused; I've always thought W-2s go to two places: SSA when the W-3/W-2s are transmitted or mailed, and the employee when they distribute them in late January.
When and where does the IRS get a copy of the W-2s? Are you speaking of when the employees file their tax returns, with W-2s attached? Or are you referring to the fact that the IRS gets wage totals and tax totals via 941s and 940?
I'm just trying to figure out how to file corrected W-2s with the IRS (ie., "all three".)

Sorry...you are correct. I'm not sure what I was thinking about there. anyway...if they haven't been filed at all (in your case), I would file the originals with SSA and provide a letter to your employees why they are receiving a second form that doesn't read 'corrected'.

Got it, thanks