I haven't got much info specifically on the Tiverton Hagleys, My family is from the Minehead/Old Cleev area from 1650 onwards. I am just beginning to suspect that they travelled up from Devon, so they could be an early breakaway group. I am currently entering onto a spreadsheet all the Hagley info from the Birth/Marriage & Death records, so I will keep an eye out for you. If you have a tree you could send me, I will incorporate it into my data. You might be interested to look at the Hagley home page - created today!