Could a new GTA Online DLC be on the brink of release? One of the telling signs that we're about to get some new content has been spotted by a few eagle-eyed fans.
In the past, every time a content update was released for Rockstar's massively lucrative Online component for the "qabeta" file was updated. This was tracked by using the SteamDB website, which displays information regarding what changes to the master-file occur for any game in Steam. This means that if the developers change the game in some way, like with DLC for example, it would show up on this site.

The last time the qabeta file was updated was right before the release of the Lowriders: Custom Classics DLC in March, when this change was also noticed by some players and news of it spread.
"But wait, wasn't that the qabeta2 file?" — I hear you ask. Yes, indeed it was, how commendable that you noticed that. You might also notice that according to the SteamDB site, the "qabeta" file without the 2 is updated pretty often.