The upsizing of Block's senior notes offering to $2 billion from $1.5 billion suggests a strategic move to strengthen its financial position by increasing its capital. This could have a neutral to slightly positive impact on its stock in the short term, as it indicates confidence in the company's future revenue streams to service this debt. However, the increase in debt load could also raise concerns about long-term financial health, depending on the company's use of proceeds and overall debt management strategy.