Vendors can deliver boats faster than the RCN can train crews
The rapid delivery schedules may not be as important as we all think
With regard to the emphasis on schedule, my understanding from media reporting is that the RCN has advised the Canadian government that both designs are technically acceptable, and that the remaining factors to decide on which submarine to procure are primarily industrial benefits and delivery schedule.
Having said that, I agree completely with you that the RCN faces a significant manpower challenge. Manning and sustaining a future fleet of 12 submarines will be exceptionally difficult unless there are major improvements in recruitment and retention. I see this, in part, as a "crisis of invisibility," and I've written a paper on that topic.
With respect, though, I think an earlier delivery of the first Canadian Patrol Submarine (for example, 2031 instead of 2032)
would actually help address the manpower challenge rather than make it worse.
If I may explain...
My assumption is that transitioning from one submarine class (such as the Victoria class) to a completely new class would likely take several years. More specifically, I believe that transitioning from one class of submarine (such as the Victoria class) to another would, unrealistically, take three years, and more likely around five years (with moderate optimism).
If either TKMS or Hanwha Ocean were able to deliver an operational submarine to Canada as early as 2031, it would allow the RCN to begin building expertise in operating, maintaining, and training on that specific class while the remaining boats are still under construction.
To crew that first submarine, the RCN would probably have to "rob Peter to pay Paul" by reallocating experienced personnel from one, or perhaps two, of the least operational Victoria-class boats. That would create the initial nucleus of maintainers, instructors, and operators for the new Canadian Patrol Submarine class.
Using the KSS-III Batch II as an example, while it requires only a crew in the mid-30s, it has an extra dozen or more bunks that could be used for trainees.
Where I think today's manpower shortage will have its greatest impact is not necessarily on boat #1, or perhaps not even on boat #2, but on boats #3 through #12. Those later submarines will require a sustained and very significant effort in recruitment, training, and retention — far greater than I fear is currently in place.
So, getting back to your original point, I believe an earlier delivery of boat #1 is one of the key elements needed to help solve the future manpower challenge. It gives the RCN more time to build the expertise needed for the new class.
The broader challenge, however, remains what you note, and what I have previously described as the "crisis of invisibility." In my opinion, unless that issue is addressed, recruiting and retaining sufficient submariners for boats #3 through #12 will remain the real long-term challenge.