Hi KenV, my comments were based on a P-8 purchase as I consider this the only sensible and least risky option to regenerate the capability. For any other option I would add at least another 3 years, however there are other factors to consider if it drags on that long such as the loss of remaining experience (not just those on seedcorn).
In my opinion this should be seen as a UOR and P-8 purchased ASAP, piggy back off the USN if practical (OCU, Sims, servicing, weapons, etc.), then bring it into core later.
IF (Big if), we get P-8s they look more expensive initially, however with their growth potential (including benefiting from US R&D) it is highly likely that they will be around for 50 years plus. I can't see any of the less capable platforms coming close to matching that.