Lots of people complaints that their hosting company claims a wrong uptime for their servers . If you notice most of they hosting provider claims 99.9% uptime which is not true because I personally experienced the same problem once . I bought hosting on digital point forum from one company though it was very cheap like $10 for an yearly hosting yet they were claiming 99.9% uptime . I bought one account from them but believe me they ruined whole of my business somehow .
I bought hosting from them and developed my business site on that host , lots of people starts complaining about my sites that it comes down when they open it , it just screwed my reputation in the market . My customers were becoming less day by day . They I noticed one day that my hosting servers get down about 3 hours a day which is just a bullshit !!
I contacted the company CEO and asked for the remedy of this case , they were still claiming that there is no downtime , I just revert my whole site to dreamhost and now I am comfortable with them . Though they charge more but at least they claims what they provide truly . So, if you are facing any kind of downtime then just change your host today because at the end of day you will be in big loss hosing your site with such crap hosts .