I assume June 7th is what you meant. It is impossible to not have a statement until July when we are still in May.
Once the purchases are paid, which has to be before the payment due date (not the statement date), the interest for this will be waived. This is because the grace period is capped to 56 days.
On June 7th, Vanquis will debt the amount of cash interest due. Provided the new balance accumulated by the interest is paid immediately, there will be no further interest charged.
If you withdraw more cash throughout next month or make purchases which aren’t cleared in full, more interest will be debited on your August statement.
All advice provided is intended for guidance purposes only. For specialized debt advice, please contact either National Debtline or StepChange.