Could be. However, I thought if it was Tier 1, it would be more ...consistent? I spend most of my time in WvW. Both of its disconnects were on Saturday. However since then to now, there hasn't been any in WvW but when I do PvE content, it could be multiple times per hour. I would have thought if it was my end or Tier 1 network, it wouldn't matter what content I was doing.
So for example, yesterday I spent 3 hours in WvW. No disconnects. I spent ~30 mins in Siren's landing & ~45 mins in Bitterfrost Frontier and got disconnected 5 times between the 2.
I was thinking it could be time of day too but Bitterfrost Frontier I did in the morning time and then went to WvW for the 3 hours and then went to Siren's Landing afterwards.
Unless I'm missing something, it just seems like it is Anet servers. It just seems like there would have to be really odd circumstances that it would happen mostly outside of certain content I'm doing.