As above; you call it an M14 yourself several times in the post and the title.
Theoretically if it was your rifle then you are currently authorised to possess it. Whether it was in your safe at home on 1 May when the Order In Council came down, or it was in the hands of the cops.
However, the way you tell it, it appears the RCMP never believed the rifle was *yours*, as they intercepted it in the import process. They consider it belongs to the importer, and thus only deal with them.
I assume the importer believes it IS yours, as they took and kept your payment? That's a pickle...
When the RCMP SFSS boys are done dragging their heels on it, they should return it to the owner. Unfortunately, it may be the case at that time that the mandatory buy-back/de-activation has taken effect, and thus either you or the importer will only get the pay-out or a welded blob returned.
(I don't know the intricacies, and I'll assume the T44E4 is not a Converted Auto or otherwise barred from import prior to the OIC. This is what the lab. was trying to determine all that time. But you did say the importer erroneously listed it as a Springfield T44E4 and call that a machine gun? How is that an error; isn't that what it is stamped? I don't see T44E4 as a designation in Section 89 of the
Schedule of the
Regulations Prescribing Certain Firearms and Other Weapons, Components and Parts of Weapons, Accessories, Cartridge Magazines, Ammunition and Projectiles as Prohibited or Restricted (SOR/98-462), or the version pre-dating the OIC.)