The Reset Date just means that on this date your accounts remaining captures, monitor checks and the scrape page limit will be replenished.
Your allocation of captures will be reset to the number of captures your package is allotted per month. So if you have a free package and your reset date was on the 3rd of September your remaining captures will go back up to 500 captures (the number of captures the free package gets per month) on this date. While your scrape page limit will also be reset to the amount specified on your package. As will the monitor checks.