You only need 1 call per possible number for each chunk, yes. But since the numbers are random between 0 to 999, that averages to 500 requests per chunk. Additionally, you don't have to do any kind of port checking for the last chunk, so that saves on any overhead you might have for the port checks. Based on this I'd say there's (3x 500 requests + 20% overhead) + 500 requests for the final block. That's 2300 requests on average.
You only need 1 call per possible number for each chunk, yes. But since the numbers are random between 0 to 999, that averages to 500 requests per chunk. Additionally, you don't have to do any kind of port checking for the last chunk, so that saves on any overhead you might have for the port checks. Based on this I'd say there's (3x 500 requests + 20% overhead) + 500 requests for the final block. That's 2300 requests on average.