Originally Posted by Michael O

If your cards expires on 08/07 your cards will work until the end of August.
A new Electron card will be send in the beginning of August, the new card will work from September 1st.
The Virtual card will be renewed on the 28th of the month and you will receive a new expiration date and CVV2.
Both cards renew automatically if the funds for the fees are available, if the funds are not available the fees will be deducted the next time your balance is big enough to cover the fees.