I “completed” an order for a refurb version of this lens in… December 2020. Still listed as “backordered.” I just assume I’ll never get it. Last time I tried to call to cancel it the wait time was over two hours.
GBC, Canon US has a super-dumb inventory system, where they assign you a particular regional warehouse and consider something out of stock for you if that warehouse doesn’t have it. If you DO call them, they’re able to get something sent to you from a different warehouse. I’ve had to do this a couple times with them.