Amovig rebound???

I have suffered with migraines (15-20 migraine days per month) for decades. And like most people on this forum have tried many treatments over the years. Nothing took them away, however, I always considered myself lucky because triptans would alleviate the pain pretty well. A year ago, my neurologist started me on Amovig injections using Nurtec for any breakthrough migraines. After a few months, this regimen seemed to be nothing short of a miracle. For the first time in decades I was experiencing 15 to 20 migraine free days per month instead of the other way around. However, over the last 3-4 months I have noticed that during the 8 or 9 days leading up to my next Aimovig injection I am experiencing some of the worst migraines I've ever had. They come on incredibly quick and are very difficult to get rid of. They never seem to completely go away even with the maximum amount of Nurtec staggered with Imitrex. The use of both medications does make them bearable, but there is some degree of pounding in my head around the clock. When I finally am able to take my next injection within 24 to 48 hours I am migraine free again... Until the end of the month. I was wondering if anyone else has experienced something similar. I'm curious because these current migraines are different than the ones that I have experienced almost my whole adult life. They feel different and in the past the pain always responded well to the triptans.