I'd just send them the last 6 months worth of statements. Alternatively, you could send nothing at all and wait to see what they ask for - but this might delay your processing. The point is to offer proof that you didn't get your current status via another status match.
Most airlines will only ever status match you once. The exception is the US airlines which have the "5 year" rule.
They won't match Velocity status.
As per the article, they specifically match any of the following statuses:
- Oneworld Emerald (e.g. Qantas Platinum, American Airlines Executive Platinum or British Airways Gold)
- Star Alliance Gold (e.g. Air New Zealand Gold, KrisFlyer Gold or United Gold)
- SkyTeam Elite Plus
- Emirates Skywards Gold or Platinum
- Etihad Guest Gold or Platinum
- El Al Platinum or Top Platinum
