Night time loss of sync

My router emails me its log and I noticed there was a loss of synch lat night. I rarely get them but normally they last a matter of seconds but last night it was five minutes.

Could this be caused by exchange maintenance? Or my ISP remotely rebooting something? I'm on an AOL/TalkTalk LLU connection.

Router log:
Wed, 2015-03-11 02:51:42 - LCP down.
Wed, 2015-03-11 02:51:49 - Initialize LCP.
Wed, 2015-03-11 02:51:49 - LCP is allowed to come up.
Wed, 2015-03-11 02:52:49 - Initialize LCP.
Wed, 2015-03-11 02:52:49 - LCP is allowed to come up.
Wed, 2015-03-11 02:53:50 - Initialize LCP.
Wed, 2015-03-11 02:53:50 - LCP is allowed to come up.
Wed, 2015-03-11 02:54:51 - Initialize LCP.
Wed, 2015-03-11 02:54:51 - LCP is allowed to come up.
Wed, 2015-03-11 02:55:51 - Initialize LCP.
Wed, 2015-03-11 02:55:51 - LCP is allowed to come up.
Wed, 2015-03-11 02:56:41 - Loss of synchronization :1
Wed, 2015-03-11 02:56:52 - Initialize LCP.
Wed, 2015-03-11 02:56:52 - LCP is allowed to come up.
Wed, 2015-03-11 02:57:10 - CHAP authentication success

Could be anything. Maintenance or your ISPs servers throwing a wobbler for a few mins. These things happen from time to time, nothing is 100% perfect

Maintenance does tend to happen in the early hours when less people are online

Probably ISP messing about with things.