For most candidates, our Social Media check will check the entire social network post history of that individual.  The check starts at the most recent post made and works back historically over time checking every post found.
We do have a fair usage policy that it is worthy to note.  This means that a standard report will check up to 18,200 posts maximum.  These are sub divided as follows:
X - Maximum of 3,200 posts
All other Social Platforms - Maximum of 15,000 posts
Over the past 100,000 reports processed, the number of candidates who had social media content exceeding this "fair usage" policy was less than 0.238% (just 238 candidates).