Is it possible to have transient thyroiditis symptoms for 4 years? can you go from one inflammatory stage to the next with hypothyroidism between?

Yes and No.: Yes you may have symptoms that look like thyroid symptoms. No they are not likely to be due to 4 years of thyroiditis and it certainly would not be called "transient" at that point. Thyroiditis - inflammation of the thyroid- may be caused by trauma / toxins/ infection or autoimmune disease. All of these processes resolve or progress within a four year span.