No. A 30-day cycle is an interval of 30 days; calendar months have different lengths. The day of the month can therefore change across renewals.
Check the exact next-charge date shown for your subscription. Product supply, your first-day routine and a delivery estimate do not by themselves establish that date. If the offer says the cycle begins at delivery, the confirmed subscription record should reflect that term.
If the offer wording and the account date disagree, ask us to check before the charge. We should not calculate a new renewal date from an example page.