United MileagePlus (Consolidated) - Paper gpu life limit

They expire on the same day as they would have if still in e-form, but is there any limit to how long the upgrade is good for on PAPER?

In other words, when I make 1k can I request a paper GPU cert and keep presenting it at the LH gate until it finally clears or expires at the one year limit?

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In other words, when I make 1k can I request a paper GPU cert and keep presenting it at the LH gate until it finally clears or expires at the one year limit?yes
expiration for paper or electronic GPUs are the same.

and yes, you can keep presenting the same one until you are successful.

If a paper GPU doesn't clear, can I convert it back to an electronic GPU?

If a paper GPU doesn't clear, can I convert it back to an electronic GPU?

Yes, would recommend sending it registered or fedex.

If a paper GPU doesn't clear, can I convert it back to an electronic GPU?

Yup...only via mail though.