I believe you are spot on about Rosh Hashanah being the second coming, it is what Matthews Gospel says to me also.
The number of days are not 2520 but the Bible says they are 2550, 3 1/2 years of 1260 days and 3 1/2 years of 1290 days. The extra 30 days is the extra Jewish month they put in place to bring all the seasons into place every so many years. Now calculate, yep the time could be very soon, according to the New moon this Rosh Hashanah September 11 which put the dates back to September 29/30, all depends where you live.
It is interesting to note, 7days before this time is the spring/Fall Equinox a very holy satanic day. This could be used as a warning from God in some way.