A maintenance on the system that hosts the uni-plovdiv.net mirror is
planned for 2015-12-22 (next Tuesday). The expected downtime is <2 hours
(most likely <1 hour) in the interval 09:00-15:00 UTC.
I'll post further notice once the maintenance is over or if the plans
mirrors.uni-plovdiv.net is down due to problems with the upstream
links. I'm afraid that at the moment no estimate on the time needed to
fix the links is available, but I expect the problem to be solved not
later than 24 hours from now.
Sorry for the inconvenience,