68, congrats on your return to training and I wish you the best in your continued recovery.
I would definitely switch to the 70.3 plan ~18 weeks before that event date, so maybe right after the June Sprint A race. Every other event between then and the 70.3 is a training day.
Of course, I note that your Oly on Oct 1 is an A race, but that is incompatible with the 70.3 3 weeks later. Sure, the 70.3 is a C race, but you really should not participate in a 70.3 using Oly training, you really need a 70.3 plan. You can certainly adjust the week of the Oly race to taper a little bit and still have a great performance.
If the Sprint and Oly A races are really A races, it may be best to drop the 70.3 altogether, as it dominates the training requirements.
David