Volume has been increasing around this $3,600 level

Could that be a sign of a bottom?

Yes, yes it could.

Prices tend to bottom and peak with larger volume than normal traded.

We aren't seeing a huge surge of volume increase just yet, but the numbers are steady increasing around these levels:

(Source: https://twitter.com/until1mil/status/1084849397492523008)

I would normally like to see a V shaped recovery but we may not get that during this recovery.

We may get a rounding bottom U shaped recovery.

I do like rounding bottoms. :)