I think Planet is not buying any shares. The opportunity to buy was when the stock was trading at $1.60. Planet spent $4 m on those trades.
What is puzzling is the new $10 m line of credit. When you think that Planet has already some $10 m in cash and the free cash-flow for this year is projected to be $7 to $9 m you begin to wonder why they need the extra money. Could it be that Planet is eyeing an acquisition? If so, this explains why the shares have been stuck here for a while.