According to Rockstar in its blog, "One thing we are already aware of, and are trying to alleviate as fast as we can, is the unanticipated additional pressure on the servers due to a significantly higher number of players than we were anticipating at this point. We are working around the clock to buy and add more servers."
Even so, Rockstar warns, "This increased scale is only going to make the first few days even more temperamental than such things usually are. This is part of the problem some of you have been experiencing with the iFruit App and some Social Club services - we apologise in advance for this and thank you for your patience in this area."
"There will be the typical growing pains for an online game, including but not limited to crashes, glitches, crazy bugs, gameplay modes and mechanics that need re-balancing and other surprises," Rockstar added. "Even in GTA5 Story Mode, some of you may have seen a few odd and even amusing little glitches out there last week. This sort of thing is inevitable in a massive open-world game and there'll surely be lots more unexpected oddities like this in the Online world next week."
"Rest assured we'll be monitoring and actively doing all we can to smooth such things out as they happen, but we need your help to find them, as well as your feedback to help fine tune all of the game's systems so everything is perfectly balanced."
Grand Theft Auto Online is due to be turned "on" on the 1st October.