I checked the logs on my mother's modem/router this morning and found that there had been 21 disconnections between 4:30 yesterday afternoon and 8 o'clock this morning. The disconnections appear to follow a pattern of some sort with intervals between disconnections of approximately 10 minutes, 17 minutes and 30 minutes occurring several times each.
I show below all of the Internet disconnect entries in the log, the first two columns are straight from the log, the third is the accurate interval between disconnections and the fourth column is my human interpretation of that interval. (I find 30 minutes easier to picture than 29:10, but notice that the simple 30 minute intervals are all within a second or so of 29:10)
02/09/13 16:30 [Internet disconnected] n/a
02/09/13 21:26 [Internet disconnected] 04:55:36 5hrs
02/09/13 23:56 [Internet disconnected] 02:29:35 2hrs 30min
03/09/13 00:26 [Internet disconnected] 00:29:10 30 min
03/09/13 00:57 [Internet disconnected] 00:29:11 30 min
03/09/13 01:08 [Internet disconnected] 00:10:41 10 min
03/09/13 01:27 [Internet disconnected] 00:17:32 17min
03/09/13 01:38 [Internet disconnected] 00:10:41 10 min
03/09/13 02:01 [Internet disconnected] 00:21:15 21 min
03/09/13 03:39 [Internet disconnected] 01:37:19 1 hr 30
03/09/13 04:39 [Internet disconnected] 00:56:28 1 hr
03/09/13 04:58 [Internet disconnected] 00:17:31 17min
03/09/13 05:09 [Internet disconnected] 00:10:45 10 min
03/09/13 05:28 [Internet disconnected] 00:17:26 17min
03/09/13 05:58 [Internet disconnected] 00:29:10 30 min
03/09/13 06:10 [Internet disconnected] 00:10:27 10 min
03/09/13 06:40 [Internet disconnected] 00:29:36 30 min
03/09/13 06:58 [Internet disconnected] 00:17:30 17min
03/09/13 07:10 [Internet disconnected] 00:10:42 10 min
03/09/13 07:40 [Internet disconnected] 00:28:17 30 min
03/09/13 07:59 [Internet disconnected] 00:17:38 17min
It looks as if it is still continuing with interruptions every few minutes.
The only computer connected to the router was turned off at about 7pm last night and back on again at about 8 this morning - so it was off during the bulk of this period. The router is protected by WPA2 so it is unlikely to be an interloper. The PPP connection seems to go down and it reconnects to a different IP each time.
I think the times are all too precise when they repeat and too wide ranging for it to be overheating or the router's software getting in a knot. I am 150miles away, so cannot easily turn the router off to reboot it - but I agree that that may be the next thing to try if nobody can suggest anything better.
Could this be Plusnet's load balancing system running amok or something that Openreach could be doing? DLM? Does anybody see the same effect or recognise the pattern?
