Ah, sure... just write a function/macro that alternates between the two instead of publishing both at once...
```
#define PERIODIC_SEND_UART_ERRORS(_trans, _dev) {  \
  static uint8_t uart_nb_cnt = 0; \
  switch (uart_nb_cnt) { \
    case 0: \
      SEND_UART0_ERRORS(_trans, _dev); break; \
    case 1: \
      SEND_UART1_ERRORS(_trans, _dev); break; \
    ... 
    default: break; \
  } \
  uart_nb_cnt++; \
  if (uart_nb_cnt == MAX_UART_NUMBER) \
    uart_nb_cnt = 0; \
}
```