Accuracy of Transit Times
Please note that the timing of transits over axes and house cusps strongly depends on the accuracy or certainty of the birth time. For example, if there is an uncertainty of only 1 minute, the exact moment of the transit can shift considerably, even by days in the case of slow transiting planets. To a smaller extent this also happens with transits over the fast planets (Moon, Sun, Mercury, Venus). This is not a problem for the astrological interpretation, because slow transits are valid for a long time. Still it would not make much sense to calculate a chart of the moment of the transit, if there is such a considerable shift.
In order to find out whether or not a transit is concerned, you can click on the blue + and move the mouse over the link "with natal chart". Then it will be shown how much the timing of the transit changes, if the birth time is changed by 1 minute. If the resulting difference is less than 4 minutes, no such information is given.