According to on-chain analyst @ai_9684xtpa they sold high on ETH to buy WBTC, then exchanged it back to ETH after BTC reached its all-time high, earning a net profit of 1533 ETH over eight months.

On 1.03.19, when ETH was priced at $3518, they exchanged 2942 ETH for 150 WBTC, costing $62,724, and also bought 116 WBTC.

10 hours ago, when BTC was priced at $98,828, they exchanged 90.8 WBTC back to 2709 ETH, costing $3312.