Oats of any kind push my BS levels up significantly. I no longer eat porridge, which I used to eat in the traditional Scots way - a little salt and cream or creamy milk. It was great, but I always felt hungry very soon after eating. Once I started checking levels after eating, I realised that even small amounts with relatively few carbs, still pushed the levels up well above where I wanted them to be.
Very occasionally these days, my level drops below 4.5, at which point I know it is in freefall so I eat an oatcake to push it back up. Today, in the absence of anything else to eat after a fasting blood test in the morning, I had an oatcake with a bowl of kale soup. Usual result - straight up to 9.6. It has taken until tonight to drop again to 4.9 and I can't go into the night with it that low, so just had another oatcake. It will be high in the morning but I can't risk it dropping any further.
Actually, oats are worse than wheat for me and wheat is worse than potatoes. So I try to avoid them all as much as possible.