AVR Freaks

It is possible that this creates two arrays: one in the static RAM that is 256 bytes in size, and the other in flash that the compiler is reserving an address for the location of the first element.  It is possible that both arrays could have the same name because they are located in different memory spaces.  Just because code compiles doesn't mean that it will work correctly.

For "tricky" AVR memory constructions, I would do a Google search for how it is done in Arduino main code files ( which are extentioned .ino) and various Arduino C++ libraries.  Then convert its format into "real" C++.  It's all GCC AVR anyway, if you're lucky.

For example, here is code for using indexed strings of different lengths which are stored in flash:

const char month01[] PROGMEM = "January";     
const char month02[] PROGMEM = "February";
const char month03[] PROGMEM = "March";
const char month04[] PROGMEM = "April";
const char month05[] PROGMEM = "May";
const char month06[] PROGMEM = "June";
const char month07[] PROGMEM = "July";
const char month08[] PROGMEM = "August";
const char month09[] PROGMEM = "September";
const char month10[] PROGMEM = "October";
const char month11[] PROGMEM = "November";
const char month12[] PROGMEM = "December";

const char * const  monthStrs[ 12 ] PROGMEM = {              
   month01, month02, month03, month04, month05, month06,       
   month07, month08, month09, month10, month11, month12 };  
   
 char * ptr, showBuffer[11];
    ptr = (char *) pgm_read_word ( & monthStrs[month -1] );
    strcpy_P (showBuffer, ptr);
    tft.print (showBuffer);