Between 1100 and about 1400 I can barely do anything with my phone.
Email, messages, Facebook IM etc... it will work fine throughout the morning and afternoon while at my desk at work but for that three hour period its a nightmare. It shouldn't matter indoors vs outdoors as it works fine any other time except for the stated 3 hour period. As far as WIFI goes.....NO. It's work WIFI and I do not want my phone on the work WIFI, I'm paying for cellular service and expect to be able to use it.
Our goal is always to make sure you get speeds you can rely on. I know how crucial that is. There are many factors that impact service and if the service is only having issues during a specific time of day, traffic is likely one of the main ones. Whether it is indoors or outdoors does still matter because signal strength is always based on a variety of factors. The signal may be strong enough at peak conditions to get through the walls, but that doesn't mean the walls aren't a factor in how it performs. Does it work better outside of the building at those times? Do you know if others there are having similar issues?