My first question - are you sure you are a Type 2? You MIGHT be a Type 1.5 (LADA) diabetic...have you had the tests to ascertain if you are? Type 1.5's are usually diagnosed around 30 and have a slowly failing pancreas - meaning that orals don't work and eventually, like all Type 1's, insulin management is needed. It's important to know if this is you, since it will mean that insulin will be needed, regardless of your weight loss.
I am a Type 1.5 for almost 26 years and insulin dependent for 25 of those. I had RNY in September 2011. I did not need insulin for the first day after surgery, and then right back on as soon as I was able to drink water. My blood sugar stayed very stable on my surgery day, but started to spike after. The good news is that my insulin needs have changed a great deal as my weight has reduced, but I still need insulin and always will. I've decreased my use of Lantus by 65%, gotten off of 3 orals, decreased metformin by 50%, but increased my bolus doses appropriately. I'm still making regular tweaks to all of this, even after 70 pounds lost and almost 9 months after surgery.
If you are not this type of diabetic, chances are you will experience what many do - you won't need insulin and that will happen very quickly after surgery. But it might be good to get this clarified now, so you can manage your own expectations about what the surgery will and will not do for you.
Here's my suggestion - take it for what it is worth - see if you can find out what endocrinologists are on staff at the hospital where you plan to have your sugery, and see them for a consult now. Since someone will have to follow you while you are in ths hospital, you might as well establish a relationship with them NOW so they can effectively help you with any management issues you will have both pre and post-surgery. I did that, as well as texted with my regular endo while in the hospital. I had to stay an extra day because of blood sugar control issues and was followed by the endocrinology group at the hospital. they were very good at working with me since I knew myself best.
Is your surgeon requiring you to get endo clearance before surgery? Maybe you already have that from the prior endocrinologist, but that's another reason I'd see the service that is at the hospital where your surgery is. I'm sure your surgeon's practice works regularly with someone, so perhaps they can suggest an endo - and maybe help to expedite an appointment so you stay on schedule with your July date.
You're also going to need to work with someone fairly closely in the weeks and early months after surgery. As your weight reduces, your insulin and medication needs WILL change, so I'd say it's worth it to see someone now and not wait. If it delays your surgery, that will be tough to take, but it may be worth it. I'm betting the surgeon's office can help you there though.
Let us know how things go please! And best of luck to you.
P.S. - Here's a link on LADA that might help you:
To determine Type 1.5, you'll want to have a GAD-65 and a c-peptide blood test drawn. There might be one other as well?