I processed a roll of Verichrome Pan that had been shot in the 1960s, and it came out with recognizable pictures, some good even.
It's a crapshoot, because you don't really know how it fared, so there will be no good recommended time for you. One developer that is pretty good with old film is HC-110. The film will have a fair bit of age fog, so the shorter amount of time it can be in the developer, the better it is. Therefore Dilution B is recommended. I would start with doing a clip test at 5 minutes, agitating every 30s, after agitating continuously for the first minute. Adjust according to the clip test.
- Thomas