DMH, congratulations on your first triathlon!
You’ll find a variety of off-season/pre-season plans in our Maintenance, Goal-Focused, Racing Weight, Strength and Mobility, Cycling and Stride Academy plans. Each plan caters to a specific need or weakness that you might have, and they range from 6 to 12 weeks in length. You can do one after the other, and even mix and match to target more than one goal at a time. I suspect that at least one or two of these plans are perfect for you to use before you start your formal Oly Training.
My recommendation would depend on your goals and fitness level. But, for example, you could start with a Build Run Endurance plan with a Swim Strong on top. Then move to a Cycling FTP Boost plan with another Swim Strong on top of that, then move to the Triathlon Maintenance plan until you start the Oly plan. That’s one of many combinations.
See https://www.8020endurance.com/training-plans/ for all of these options.
David