I'm late on this post ... but my story.
Diagnosed as type 2 at age 45 based on symptoms and glucose tolerance test. Not a blood test. Endo put me on metformin and I lost weight and upped my exercise. A1c, even at the beginning was mid 5's. Eventually, the A1c started to increase. I blamed myself; I should exercise more, lose weight, etc. Endo change metformin to some other oral meds. The disease kept progressing. Endo eventually put me on Lantus which worked for about a year, then he added another injectable. and I was increasing dosages.
My son was home for a couple weeks between medical school and residency. He asked me what test my endo did to diagnose. I told him none. He said it's odd that for the past 10 years I've lost weight, exercised more, changed my diet .. etc. He handed me his phone with an article about LADA. It described ME. Was seeing endo in a week so I told him I wanted a GAD test to see if it was LADA.
The test came back for positive for antibodies and endo changed diagnosis to T1. Then told me the treatment is the same for T1 and T2, so knowing really didn't change anything. I told him the past 10 years of self loathing and blame are gone. It's not my fault. I will always be insulin dependent. So, while it changed nothing for him, it took a huge weight off of my shoulders.