Thanks would be 7 down to 4
that could significantly change the size of the table allocated by the restaurant
parties of 6 and more are automatically charged the 18% gratuity. IDK if it's still the case if less than 6 persons show up.
Anyway there is no issue booking for 7 and only showing up with 4 guests. You won't get charged for the no shows.
but I would still try to change the ressie for courtesy towards the restaurant
do a new ressie, for the same restaurant, same time, and only 4 people. WITHOUT cancelling your original ressie first.
If you're successful in finding a table at that restaurant, and your second ressie conflicts with the first, the system will ask you if you want to replace the old reservation by the new one
if you choose to replace, then the system will cancel the old one once the new one is done.
If the system doesn't prompt you for a reservation conflict, then book the new party, and then, only then, cancel the old ressie
this way you don't risk not having your ressie for that day and that restaurant
if there is no available table, just leave it at 7
don't cancel anything until you're successful booking a replacement.