Unfortunately, the specificity of your upcoming training demands that you develop and train in a way that is directly applicable to what will be required of you. There is no way around it. That said, specificity in training can often be delayed until a few months or weeks out from the event. As you may know, being a successful SF operator, and being successful with their training, depends more on ‘grit’ and ‘mental perseverance’ than aerobic and/or anaerobic conditioning per se. Granted a certain baseline level is required, but this baseline is not what causes candidates to drop out. Based on what I can tell from your post, you probably already have this covered (excluding perhaps specificity).
Rowing is a great aerobic/anaerobic conditioning exercise. It is quite non-specific, however, for the in-service training you are about to undertake. Therefore, it should likely be phased out as you ramp up specificity.
More specific answers to your training questions are hard to provide based on the limited info in your post. I would encourage you to hire a coach (if possible) and not just use a training plan template (unless you enjoy self-coaching with its pros and cons). Your training is obviously very important to you–it’s your career, and perhaps your life is eventually at stake. You will also be training in a similar fashion for years to come. I think an initial investment in a coach (preferably one with experience training tactical operators), at least until your service starts, could go a long way in helping you be successful. It may also be tax deductable, who knows!
Best of luck. I hope this helps somewhat.
PS – which branch of service/program are you entering?