Website goes offline on my ISP (only!) after an update is done (strange!)

Hey everyone,

This has to be the strangest issue ever. The other week I saw that 5 updates of themes and plugins had to be done, so I did them as normal. The plugin was the P3 (Plugin Performance Profiler). After updating those things, my site went down. I asked a few people on different ISPs and checked via 3G and it was down as well.

I spoke to my web host and they checked and found an apache instance failed and they restarted it. It was then back up again. I didn’t think anything of it.

Then… a few days later when I updated more plugins, the exact thing happened again. I spoke to Dreamhost thinking that apache failed again and they said it was perfectly fine. I asked friends to check, and it was working for them on their ISPs, on 3G my site loaded (not a cache version) and that confused me.

It’s since happened 3 times and again today when updating to 3.9.1. After updating it, the site goes down on the ISP that I’m on (for everyone connected on that ISP). I’ve test of different ISPs (to rule out an ISP issue) and every time I update something, my site goes down on any ISP I’m on, but works on 3G and other ISPs for other users. It’s not my laptop either as I tested on numerous laptops at the same time. It eventually comes back live when I reboot the router a few times.

This is confusing the hell out of me and was working if anyone has seen this before? If so, what on earth to do about it?!

[Moderator Note: No bumping, thank you.]