Yes getting your traps to fire is key. Most triathletes do not swim so that their traps fire. Thus building up this strength now is vital and will help you fire them when you get back in the pool (and your form allows for them to fire). Good body position and a high elbow catch will help here so now is the time to focus on these key elements.
As for your question, I am sorry I don’t understand. You are on week 6 of training but you want to know how to sub it in for week one? What training plan are you currently doing that you are on week 6? Given your question here about transitioning back into swimming, I will try to best answer for all to learn.
When we are able to transition back to pool swimming (or open water), we will all be confronted with how to do so without being able to swim for weeks or months. So the reentry will be important so you don’t injure yourself. This will look different for everyone given your background in swimming, your current conditioning (keeping up with dryland work, etc). Obviously what you want to do is weigh on the side of not doing too much too soon.
Thus after the off season is over and you decide to hop back in the pool, where would you start? 30 minutes of easy lap swimming focusing on different drills? 1200 yards of a structured swim workout? This is a good place to start as a barometer of where you should start again. Then build from this point. If you start at 1200 yards, next workout would be 1400 and so on. You could also go back to the start of your training program and do as much of the swim workouts as you can without overdoing it.
There is no clear cut answer here. This will be different for each one of you. However this is a guide to help you ease back in to what feels right for you.
Great question Brett! Let’s hope this is a positive sign as to what is to come 🙂