I wonder if the operation addObjectsFromArray happens in constant time

gistfile1.m

- (void)createWallOfFame:(NSArray *)newWallOfFameMembers
{
    NSLog(@"add %i new member(s) into wall of fame", (int)newWallOfFameMembers.count);

    NSMutableArray *currentMembers = [NSMutableArray arrayWithArray:self.members];
    if (currentMembers.count > 0) { // only if members are available there is a reason to delete them an the end
        NSRange rangeForMembersToDelete = NSMakeRange(currentMembers.count-newWallOfFameMembers.count, newWallOfFameMembers.count);
        NSLog(@"delete members from position: %d with length: %d", (int)rangeForMembersToDelete.location, (int)rangeForMembersToDelete.length);
        [currentMembers removeObjectsInRange:rangeForMembersToDelete];
    }
    
    NSMutableArray *newMembers = [NSMutableArray array];    // create a new array and insert the new members at the beginning.
    for (NSDictionary *dict in newWallOfFameMembers) {
        BKErsteReiheMember *ersteReiheMember = [[BKErsteReiheMember alloc] initWithUserInformation:dict];
        [newMembers addObject:ersteReiheMember];
    }
    
    if (newMembers.count < [kMaxWallOfFameMembers integerValue]) {    //  Afterwards add the old entries behind the last new member
        [newMembers addObjectsFromArray:currentMembers];
    }
    
    self.members = newMembers;
    [self saveMembers];
   
    NSLog(@"number of members in wall of fame: %d", (int)self.members.count);
}