Titleist builds to what the order says. Many of their heads are already built to standard or 2 degree upright or 2 degree flat. As they assemble each club they adjust the bend tolerances to make sure each head matches that order. These are fractional adjustments. Cast heads can be bent up to 2 degrees but if not careful, the hosel can crack. Make sure if you take your clubs somewhere to have the lofts or lies adjusted, that they have a guarantee in case any are cracked. Titleist offers this service too. Contact the warranty/care/repair link at the bottom of the website.

All lofts and lies can be adjusted at any shop that has a loft and lie machine. Typically, Mitchell based clamp system. There are a bunch of other brands in the market now but it's very common.

Typically, you don't want to make a 4* plus change but it can be done. Especially with forged clubs. Cast clubs are a bit riskier to make severe adjustments. I've never had any clubs break when I was a fitter but just words of caution.

But 2* I don't' see why not. Should only take about 30 minutes to an hour max to do a set of irons if you find the right place.

In the past I have been advised by Titleist that do manufacture heads at standard lie plus 2 degrees upright so with both to be adjusted +/-2 degrees only, thus, giving 2 degrees flat and 4 degrees as options. It is also possible that as Dale states that they also manufacture at 2 degrees, but, I really don't know. Here is the reply I got from Titleist:

Cathi, Titleist Club Concierge
4 JANUARY 2018 AT 10:11AM
Hi Joseph, The AP1 as well as AP2 and T-MB heads are built at std lie as well as 2° upright so we only bend the iron 2 degrees. We don't encourage players to have their heads bent outside of our facility (it voids the Warranty) so we provide the specifications that we will build for custom orders