Name of your Internet Service Provider (ISP): Comcast

Ticket or reference number from your ISP: CR534611724

State/Country: Indiana/USA

Date/Time (When did the issue start happening, at what specific times does this issue arise, if any.): Thanksgiving weekend and "cyber monday" were the worst, and it has tapered off since then, but it's still noticeable during evening hours and on weekend afternoons

Frequency (How often does the issue occur?): Generally in fits and starts, where for a few global cooldowns (maybe 10 seconds total, then)? The game will not exactly freeze, but act similarly to as if network connection were dropped (other characters stop taking actions, skills do not have effects, etc), then for another 10s or so after things start back up, a bunch of things that happened during the slowdown period will finally apply. Generally happens a few times a dungeon, so assuming a dungeon takes maybe 30m, that would be once every 5-10m? This is all during "peak hours", in the early morning when no one is on, it runs butter-smooth.

Content (Which content were you playing in-game when the issue occurred?): Nothing in particular; a few dungeons, running around Idyllshire, bit of crafting and gathering...

Which in-game World were you playing on when the issue occurred?: Diabolos

Traceroute records (optional)

One I generated while the issue was tapering off, a bit laggy but not as bad as during peak times:

1 1 ms 1 ms 1 ms 192.168.8.1
2 161 ms 35 ms 62 ms 96.120.112.129
3 11 ms 10 ms 16 ms te-0-0-0-6-

sur04.noblesville.in.indiana.comcast.
net [69.139.173.185]
4 10 ms 11 ms 10 ms te-8-3-

ur03.elmhurst.il.chicago.comcast.net [68.
87.231.133]
5 12 ms 11 ms 11 ms 69.139.202.213
6 25 ms 23 ms 23 ms hu-1-13-0-0-

ar01.area4.il.chicago.comcast.net [6
8.86.187.245]
7 * 62 ms 22 ms 4.68.63.125
8 233 ms 234 ms 220 ms ae-10-

10.car2.Montreal2.Level3.net [4.69.153.86]

9 177 ms 162 ms 107 ms ae-10-

10.car2.Montreal2.Level3.net [4.69.153.86]

10 50 ms 42 ms 43 ms ORMUCO-

COMM.car2.Montreal2.Level3.net [4.59.178.
74]
11 42 ms 41 ms 42 ms 192.34.76.10
12 278 ms 302 ms 320 ms 199.91.189.242
13 46 ms 44 ms 89 ms 199.91.189.38
Subsequent pings to stops 7 and 8 showed that 7 was fairly normal ping and 8 occasionally had spikes of >600ms ping, without noticeable packet loss.

One taken now, late at night:

1 <1 ms <1 ms <1 ms 192.168.8.1
2 9 ms 8 ms 9 ms 96.120.112.129
3 16 ms 10 ms 8 ms te-0-0-0-6-sur04.noblesville.in.indiana.com
net [69.139.173.185]
4 9 ms 9 ms 16 ms te-8-3-ur03.elmhurst.il.chicago.comcast.net
87.231.133]
5 13 ms 15 ms 14 ms 69.139.202.213
6 25 ms 23 ms 30 ms hu-1-13-0-0-ar01.area4.il.chicago.comcast.n
8.86.187.245]
7 2248 ms 2136 ms * 4.68.63.125
8 42 ms 42 ms 49 ms ae-10-10.car2.Montreal2.Level3.net [4.69.15

9 42 ms 42 ms 42 ms ae-10-10.car2.Montreal2.Level3.net [4.69.15

10 48 ms 45 ms 43 ms ORMUCO-COMM.car2.Montreal2.Level3.net [4.59
74]
11 40 ms 40 ms 73 ms 192.34.76.10
12 40 ms 40 ms 41 ms 199.91.189.242
13 52 ms 40 ms 42 ms 199.91.189.38

Trace complete.
A couple more showed packet loss at stops 7 and 8, which seem to be the worst for my location.