Unfortunately, I have serious doubts about the whole thing
Because the literature states that this Seguloh is unique to Tu b’Shevat {Something along the lines of the fruit being fruitful and getting married to be fruitful} so either:-
1) Are they blowing the 1000 Shoforos on Tu b’Shevat on Shabbos? Certainly, 1000 people is enough to make a Sanhedrin.
2) Are they blowing the Shoforos on some day other than Tu b’Shevat so as not to carry 1000 Shoforos to Amuka in a Reshus hoRabim on Shabbos? thereby missing the Seguloh date of Tu b’Shevat.