I cannot say the opposite, I read this link Arduino Playground - Memory and I understand that 32k are available for User Program. The previous sketch was filling flash for 29k and the new one for 23k. This has been the reason of change. Because,in future, I will may want to copy some variable in the flash memory with avr/pgmspace.h library using strcpy_P function to keep the SRAM free.
Sorry for BUFSIZE
#define BUFSIZ 100