Using a RA lifetime of 1800 seconds on br-lan in logs

I've been having some problems with my IPv6 connectivity (it seems to time out eventually for clients as though they lose their routes or something) and I'm trying to diagnose what's going on.

I just did a build of LEDE today and now I am seeing a lot of these messages in the log files:

Mon Apr  3 15:30:42 2017 daemon.info odhcpd[1430]: Using a RA lifetime of 1800 seconds on br-lan
Mon Apr  3 15:30:46 2017 daemon.info odhcpd[1430]: Using a RA lifetime of 1800 seconds on br-lan
Mon Apr  3 15:30:50 2017 daemon.info odhcpd[1430]: Using a RA lifetime of 1800 seconds on br-lan
Mon Apr  3 15:30:54 2017 daemon.info odhcpd[1430]: Using a RA lifetime of 1800 seconds on br-lan
Mon Apr  3 15:30:58 2017 daemon.info odhcpd[1430]: Using a RA lifetime of 1800 seconds on br-lan
Mon Apr  3 15:31:02 2017 daemon.info odhcpd[1430]: Using a RA lifetime of 1800 seconds on br-lan
Mon Apr  3 15:31:06 2017 daemon.info odhcpd[1430]: Using a RA lifetime of 1800 seconds on br-lan
Mon Apr  3 15:31:10 2017 daemon.info odhcpd[1430]: Using a RA lifetime of 1800 seconds on br-lan
Mon Apr  3 15:31:14 2017 daemon.info odhcpd[1430]: Using a RA lifetime of 1800 seconds on br-lan
Mon Apr  3 15:31:18 2017 daemon.info odhcpd[1430]: Using a RA lifetime of 1800 seconds on br-lan
Mon Apr  3 15:31:22 2017 daemon.info odhcpd[1430]: Using a RA lifetime of 1800 seconds on br-lan
Mon Apr  3 15:31:26 2017 daemon.info odhcpd[1430]: Using a RA lifetime of 1800 seconds on br-lan
Mon Apr  3 15:31:29 2017 daemon.info odhcpd[1430]: Using a RA lifetime of 1800 seconds on br-lan
Mon Apr  3 15:31:33 2017 daemon.info odhcpd[1430]: Using a RA lifetime of 1800 seconds on br-lan
Mon Apr  3 15:31:37 2017 daemon.info odhcpd[1430]: Using a RA lifetime of 1800 seconds on br-lan
Mon Apr  3 15:31:41 2017 daemon.info odhcpd[1430]: Using a RA lifetime of 1800 seconds on br-lan
Mon Apr  3 15:31:45 2017 daemon.info odhcpd[1430]: Using a RA lifetime of 1800 seconds on br-lan

Notice that these messages are only a couple seconds apart. They certainly aren't anywhere near 1800 seconds. What is causing odhcpd to reset the RA lifetime so often? What would cause it to not wait the 1800 seconds? Is there a chance this is a factor in why my connections seem to keep timing out?

I did too had problems in losing ipv6 but it seems it was a Windows problem, updated to win 10 to that machine because it was long overdue, had it installed since 2010

This is happening mainly on my iPhone.