Indeed -- I can't imagine given the release date that rules themselves are up for debate in anything but loophole closure. Anything else would invalidate a lot of Tier 1 test work.
Playtest tier 2 would only be able to get at individual ships, and, even then, it's getting FAR too late.
In the Chicago area we might --- might! --- be able to summon up 16-18 players.
Functional testing would then occur by having a fleet of 5 each ship (possibly including a breakdown to get a Scout on the table) vs. 5 of another ship of the same priority. You' run each 1-ship fleet 3 time, minimum, using different players each time (to at least attempt to divide out for player skill variances within the playtest team). So each ship would need three tests. Then, take all the results for the Raid-level ships, put them in either a RPI or ELO calculation system (ELO is probably better with larger sample, RPI is probably better with a small sampler) and generate an RPI rankings. Ships at the top and the bottom end would then be eligible for edit.
Scouts themselves would be excluded (no reason to take a fleet full of scouts). Dedicated carriers, I'd exclude initially as the playtest group would likely need some time to adapt to the new fighter tactics the rules would suggest. I'd also do Armageddon ships last --- they're not used nearly as much over the table (our experiences).
To do this WAY TOO SPARSE unit test, we would need at least 3(number of games) x 1/2(2 players per game) x appx. 210 ships = 415 games to be able to make reasonable statements about the product's balance. With a team of 18 people, which the Chicago area MIGHT be able to summon up -- barely ---, that's 9 simultaneous games; we'd need about 415/9 = 46 sets of games and a big post-mortem meeting to be able to contribute with reasonable authority. If the target release date is August 20, and we fantasized that last-minute changes would only require 2 weeks before printing (not bloody likely!), we'd need 7-8 games per player, per week, to be able to help at this point. And this test would not even Begin to deal with:
--- Balance of Swarm Fleet vs. Big Ship
--- Fighter Balance
--- League Whole-Is-Better-Than-Sum-Of-Parts Phenomena
--- Refit and Duty Tables
--- Campaign Structure Changes
--- Typos
--- Clarifications
If the second wave of playtesters got the product in May or so, there could have been a lot of positive impact; but I think the clock has run out.