I do not know what inhaler you're using and whether or not you have refills remaining on your prescription.
I do not know if you are out of state or simply from another Californian city.
All I know is that you may possibly be making this situation more difficult for yourself than it should be. If you usually fill your prescriptions at Walgreens, then they should be able to transfer that script electronically to any location (barring any issues with controlled medications and lack of refills) and fill it, whether or not your insurance will pay for it. Most insurances will grant a courtesy yearly ONE TIME early refill for a variety of reasons per medication, including vacation fills. Unfortunately some insurances do not cover early refills for ANY reason but it does not mean you cannot pick up your prescription. I cannot imagine a single pharmacist who will bother refusing to fill an inhaler early.
As a pharmacy, we have access to certain numbers by the insurance company that are specifically meant for us. When you tell me you need an early refill for any reason at all, then I will be the one to call your insurance company to receive that override. If your insurance refuses to pay then I'll just give you a substantial discount (even more if you aren't a dick) because there are ZERO benefits to me withholding your medication and I do not care about profiting from a few dollars when we already fill hundreds of prescriptions daily.
The only time you should bother calling your MD is if you're prescribed an expensive ass inhaler like QVAR RediHaler, which I know for a fact costs hundreds of dollars out-of-pocket. At this point an entirely brand new prescription is required and not only do you have to wait for the MD's response, but there's a chance you might be prescribed an alternative that isn't even covered or has an insanely high co-pay. This involves more waiting if you're even lucky enough to find a pharmacist who will bother running test claims for you.
I can't offer you anymore information than this because you did not state which inhaler you're using or your prescribed instructions. Make life easier on yourself by communicating with your pharmacy.