I reached out to NCDOT a few weeks ago in regards of I-587 and what might happen to US 264. I got a response today that they are indeed planning to submit a rerouting to US 264 and a elimination of US 264 ALT in the AASHTO Fall Meeting. They were even kind enough to share the draft files they plan to use in the upcoming meeting.
In the requests, they will relocate US 264 along existing US 264 Alt from Exit 51 south through Saratoga and Farmville, then in Greenville it will connect onto NC 11 Bypass north, a total of 26.43 miles relocation; that section of US 264 Alt will be eliminated.
The timeline after that depends on other factors, but they hope to have I-587 and US 264 signage done in 2022.