For the record, the blood test not even close to 99.9% accurate, though the swab test is much better.
The IgG for HSV 1 misses 30% of HSV 1 infections so that could account for the change in HSV 1 status. You could consider coming off the suppressive therapy for 3-4 months. If you have an outbreak during that time have it swab tested – again. If positive again, there is no need to stay off suppression. If you don’t have an outbreak, you could continue to stay off for the 4 months and then do the blot. If you are having sex with someone who is negative for HSV 2, this will increase the risk that you could infect them. Alternatively, you could accept the HSV 2 swab test as accurate, understanding that being on suppression this long could be impacting the IgG results. If you concern is that the swab test was somehow inaccurate then doing the blot is the right thing to do.