CRA finds that entering into an agreement to pool administrative support services triggered an obligation to register for GST/HST purposes
A non-resident insurer which otherwise was only making exempt (insurance policy) supplies in Canada was found to have been required to register for GST/HST purposes as a result of entering into an agreement with another party under which each agreed to provide administrative services to the other at cost, to be billed annually. ETA 136.1(2) typically deems periodically billed services to be supplied at the beginning of each billing period, so that presumably the effective date of required registration was the effective date of this administrative services agreement.
Neal Armstrong. Summary of 30 August 2018 Ruling 185770 under ETA s. 240(1).