I think the scammers are using 301 306 and miscellaneous 4 numbers to get around "reporting sites" like 800 notes.  I have received hustles allegedly  from these numbers for various scams, i.e. "final arrangement insurance", "reverse mortgages", "free solar", etc. etc. - whatever the scam de jour is.  So far, I haven't seen anyone (besides me) reporting these Pakistani's allegedly using these phone numbers.  I sincerely hope that does not mean they are being successfull !!