According to divisional Vimshottari system in JHora-7.51, esp in SSS mode, D60 Vimshottari will show a difference of 300 days, on an average, in timing of events, even if D60 and all other charts are identical, if birthtime differs by only one minutes. But twins differ by greater margins. Hence, many higher
divisional charts differ and their Vimshottari timings differ by many years. There are other fine nuances too. Eg, solar return charts will differ almost by same duration of time as in birthchart, and therefore higher divisionals in varsha phala or maasa/pratyantara phalas will differ considerably, so that birthchart differences will get added layers of differences in charts as well as in their timings.
-VJ