I don't know what is acceptable to me. My blood sugar this morning was 24.9 and I tested again tonight and my blood sugar is at 15.4. I am only able to test twice a day on a weekday and once a day on a weekend, due to only being prescribed 50 test strips a month.
I'm on a limited budget and bran flakes is the least carb cereal that I can think of.
I see you are in the UK.
You need to arm yourself with legislation knowledge when dealing with your GP and healthcare.
Firstly, you shouldn't be paying for prescriptions - Diabetes is an exempt condition.
Next, NICE guidelines say intervention is required if BG is over 15.0 because of the underlying damage it can cause - neuropathy, retinal damage, kidney and liver damage, periphery damage and so much more.
There is so much legislation that demands you are treated correctly starting with the Equality Act that requires reasonable adjustment to keep you healthy. I am prescribed 300 test strips a month and just request more if I need them; I also have a supply of ketone testing strips to use on 'sick days' (testing ketones is part of the 'Sick Days' rules for ALL diabetics.
Limiting access to health care is illegal - look to National Care Standards, Patients Rights Act, Human Rights Act and many others.
If you have problems representing yourself (I noted on responder who is hampered by Asperger's - my Asperger's makes me a pain to officialdom because I research my rights before contacting them as my experience is they try to screw me over) contact your local authority to access Advocacy representation. Mental health issues are a common comorbidity of many conditions including diabetes and qualifies for free support.
Do not accept poor treatment for any reason. Lack of funding rarely affects frontline delivery of service but is used as an excuse for bad practices.
Remember you have rights protected in law, and any practice that impacts your life quality or life expectancy should not be accepted.