[Proziam]

The price sensitivity thresholds of your median customer is not likely to be a factor in this range.

What is a factor is 'getting a deal' and customer conviction. You want to give them an offer that makes them feel good about signing up immediately (increase conversion) and makes them feel like the product has substantial long-term value (induces post-purchase rationalization).

The annual plan with significant sale price accomplishes both goals, with the benefit of smoothing out your revenues and making it much easier to estimate your ROAS.