Hi Christopher.
Having a further look through the site you recommended i found 3 women matching Michaels details, (area, place of signing, agent). Michaels entry didn't show an address.
The women were:
Roseann, Quarry St, Portrush
Martha, 11 Kerr St, Portrush
Mary, Sheer St, Portrush
The more i am looking, i reall think this is the family of the Isabella mentioned by Audrey. I have nothing on paper to show Isabella was from Belfast. The only confirmation of this information was from my Aunt! I would really like to hear what you think and any suggestions on where to go from here!
Many thanks for alll your help so far.
Amanda