Comcast XFINITY → [E-mail] Intra-comcast mail server delays?

A strange delay this morning on Comcast mail - what was it doing in Comcast-land for seven hours before delivery?

Other emails (from other senders) were coming through like clockwork.

Received: from reszmta-ch2-06v.sys.comcast.net (LHLO
reszmta-ch2-06v.sys.comcast.net) (69.252.207.70) by
resbmail-ch2-02v.sys.comcast.net with LMTP; Fri, 12 Dec 2014 18:40:42 +0000
(UTC)

----> 7 hours and 11 minutes to get from one Comcast mail server to the other


Received: from resimta-ch2-19v.sys.comcast.net ([69.252.207.19])
by reszmta-ch2-06v.sys.comcast.net with comcast
id SbV41p0010Resgd01bVNiK; Fri, 12 Dec 2014 11:29:22 +0000

Received: from umgah.mesas.com ([65.245.16.9])
by resimta-ch2-19v.sys.comcast.net with comcast
id SbV51p02b0BkBl501bV54k; Fri, 12 Dec 2014 11:29:21 +0000

strange, i saw the same kind of delay with some messages today on my personal mail server hosted on a BCI connection. Though it was likely just a coincidence with the issue you noted with Comcast hosted email