A taxpayer does not get to pick and choose which tax year they want to take losses.
Losses need to be taken, assuming allowable, in the applicable year.
While we don't have any facts, it is most likely you are able to utilize the S corporation losses on your personal tax return.
As such, I would recommend you prepare your 1040 without any S corporation losses, file an extension, pay any applicable taxes, finalize your S corporation return, add your K-1 details to your 1040, file your 1040.
*A reminder that posts in a forum such as this do not constitute tax advice.
Also keep in mind the date of replies, as tax law changes.
