Oklahoma 87

[bugo]

According to signage, this route ends at US 259.  However, most maps and ODOT documents have it continuing along 259 to end at US 70 bypass.  This is likely a relic of the time before US 259 was commissioned circa 1963, when the entire highway was OK 87 and the Red River bridge didn't exist.

[Scott5114]

Control section maps show it as ending at 259, same as signage. So I'm inclined to believe that is its "official" terminus. Otherwise, your research matches mine.