You may find it most relevant to use baby's due date/adjusted birth date, rather than birth date, to adjust the recommendation appropriately. We recommend basing their Play Kits subscription on their 40 week due date or adjusted birth date. Once you have subscribed, if you find your little one is ready to tackle the next Play Kit early or needs a little more time with a Play Kit, you will be able to make adjustments to your shipping schedule within your Lovevery account. For more specific guidance, please contact us.