CRA maintains its restrictive position respecting the GST/HST exemption for supplies of goods before their release

ETA s. 144 provides that “a supply of goods that have been imported … but have not been released [by the CBSA] before the goods are delivered … to the recipient of the supply, shall be deemed to be made outside Canada,” so that even if the vendor is a registrant, it is not required to charge GST/HST.

CRA considers that s. 144 does not apply if the goods were supplied by the vendor before they were imported and, in this regard, applies ETA s. 133, which deems goods to be supplied at the time that the sale agreement is entered into. Accordingly, in an example where a registered non-resident enters into a somewhat long-term agreement for the supply of fuel oil to Canco, and thereafter delivers the fuel oil to Canco at a Canadian port, CRA considers that s. 144 does not relieve the non-resident from the requirement to charge GST/HST notwithstanding that the fuel oil has not yet been released at the time of its delivery in Canada.

Neal Armstrong. Summary of 8 September 2017 Interpretation 180362 under ETA s. 144.