A counterpoint, well, sort of ... to yesterday's post is : you should get answers to your unknowns ASAP even if those are hard to get.

You don't want to spend time making progress on anything unless you know that reaching the goal is achievable within your constraints.

Don't loose track of what matters. Confirm what you can and need in order to proceed. Or, at least have a reasonable amount of certainty that what you want to do is indeed possible.

If not, don't despair, work towards alternatives. What can be a good intermediate solution that can bring you 90, 80, or even 50% of the way. That can be a win too.

Knowing that you can't achieve a particular goal before investing too much in it is also a win in itself.