> ...but in my world that excuse runs out waaaaaay before 15 months.

I expect the combination of

  Yes, we should've migrated away sooner, we never had the capacity to do so and hoped Bunny would just get their shit together.

and

  The loss rate isn't enormous in percentage terms, but it's consistent and ongoing.

means that detecting and dealing with the loss is substantially less work than moving away. [0] I expect that Management is fully aware of what's up and is making the call here.

[0] "Just" add a retry if the post-upload verification step fails! Sure, it's slower, but it works, right??? mournful sob