What is the meaning for this sentence?

 "Thank you for the weekend offer - hope we don't need to tap you too much. Time goes awfully fast. I knew you'd been on board for a while, but didn't think it was that long."  

I can understand the first and second sentence. I wanted to know more on the last part. What is the meaning? Is it positive or negative statement?

Anonymous2021-04-11T16:16:06Z

It's positive.  The original offer to be available or make something available on the weekends was made some time in the past.  That's why the writer remarks, "Time goes awfully fast," in order to acknowledge that when people offer up their services they usually have a finite amount of time in mind.  The writer is expressing pleasant surprise the the offer to help still stands after a period of time that's considered longer than usual.  The writer does not say so directly but you can tell that he or she thinks that the person they are writing to is a generous person.