Bernard:
No advantage really. I have not seen any other mention of that term in association with Burtles, Tate & Co. Maybe somebody has come across an ad or old trade journal article that can help with the dating.
There are many nuggets of information in the Glasfax newsletters but nothing related to this topic. Glasfax is a Canadian organization dedicated to the study of glass manufactured and used in Canada from before Confederation right up to the present day. Our focus was, is and will continue to be mainly on glass in Canada. Being related in some way to an evacuee is not a pre-requisite for membership - obviously because they let me in. We have just recently developed a web based archive of all of the newsletter that is only available to our members. We have members from outside of Canada.
And no, I didn't expect that!