When did the Early Church begin and end their twice weekly fasts?

In the Didache , it tells us "8:2 but keep your fast on the fourth and on the preparation day (Friday)." Obviously some actually did keep these weekly fasts, when exactly did they begin and end? Did they eat Tuesday supper and not eat again until Wednesday supper? Or did they eat Tuesday supper and end the fast the morning of Thursday so that no food was consumed Wednesday? Or Wednesday morning to Thursday morning etc? I reckon the times of these fasts were in line with the twice weekly fasts of the Jews who did theirs on Monday and Thursday. Can anyone provide more clarity on this?