I have heard from my tax guy about the 174/162 treatment and "new" cos vs "carrying on trade" cos and his read is that it's defensible to continue using the latter provision especially given one has actual revenue associated directly with that activity as of year 0, rather than some kind of 80s style "we will spend two years building the software and then three selling it in boxes" that is more directly analogous to capitalizable costs. It happens all the time that CPAs are overly focused on particular provisions phasing in and out vs a holistic view of what provisions even apply.

Keep talking to CPAs until you find the one willing to engage in sufficiently aggressive tax treatment to not bankrupt your company. Tax returns are not footnoted; you're not required to explain at time of filing what exact reading of your activity and the tax code leads you to believe you have a vanilla payroll expense vs a capitalized R&D expense.