I had a moderate tear of medial head of the gastroc. Tested every ounce of patience I had.
Took me a good month before I could even play and that was very limited. A little mini tennis, very light hitting from the middle of the baseline. Gradually, I got better, but the key, even though you're back on the court, is not to not push it.
First the muscle has to heal, then you have some rebuilding to do as far as stretching and strengthening and getting your body back into tennis shape. For me, I really didn't make significant progress until I started weekly PT --- and that was a month after the original injury.
I just started playing tennis about two years ago, but the torn gastroc made me appreciate the game --- mainly how tough it is on your body and why pros generally don't have real long careers. Not only do you have to stay in shape, but you have to take care of your body for the long haul, even at the rec level, IMO.
If I were you, I would use this 'off' time to ride the stationary bike (to try to maintain conditioning as much as possible) and incorporate a complete stretching program, not just the calves, everything, hamstrings, glutes, quads, hips, shoulder, etc. I've found the more flexible you are, the easier tennis is on your body.