Registration 80-1071
Alt 21500' (+0 fpm)
Flight no
Recd. at 140430 192707
ICAO id AE0954
Type U2

Looks like this could have been the chap.
He maxed out at 22,800 feet at around 1920 GMT loitered there for a short time then RTB...whole flight was just over an hour.
No climb to "above" FL600 as far as I can see.
The altitude reports during the flight were consistant with a gradual climb to 22,800 then gradual descent....so that rules out the problem with the computer system being unable to handle anything above FL600

The regs of U2s are not reliable in Mode S as the boxes seem to be rotated

Were ATC expecting a climb to 60K and got confused when it didnt
climb that high , or was the flight curtailed when the confusion broke out ?

A Federal Aviation Administration computer system interpreted the U-2′s flight path at a very high altitude as if it were flying in a much lower and more crowded airspace

Hmmmm ..... Its Mode S must have been very wrong.

Of course the data I have might be a totally separate flight , but it does seem to fit the profile.

There's an interesting article here that discusses in some detail the cause of this outage and the limitations of the ATC computer system:
Exclusive: Air traffic system failure caused by computer memory shortage | Reuters