East Japan Railway Co said it hopes to have all its bullet trains running full service routes by the end of April.
The 11 March, 9.0 quake damaged East Japan Railway rail lines in at least 1,200 places. About 45% of their routes are operational.
In other parts of Japan the problem is still lack of electrical power. That will continue for longer than expected, due to the fact that at least three nuclear power plants are shut down, not counting Fukushima Daiichi.
In northern Honshu, as I posted in an earlier report, 40 year old Diesel engines were brought out of retirement, saved from the scrap heap, to run supplies into the areas of devastation. That may not last long either, due to lack of fuel.