Another way to look at this :

DVB-T modulator maximum play rate depends on code rate, constellation, guard interval, bandwidth.
The maximum bit rate can be calculated as below.

Tbandwidth = {6,000,000, 7,000,000, 8,000,000} in Hz for 6MHz, 7MHz, 8MHz
Tcode_rate = {1/2, 2/3, 3/4, 5/6, 7/8}
TConstellation = {2, 4, 6} <- QPSK = 2, 16QAM=4, 64QAM = 6
TGuardInterval = {4/5, 8/9, 16/17, 32/33}, 1/4 = 4/5, 1/8 = 8/9, 1/16 => 16/17, 1/32 => 32/33}
2K/8K mode does not matter

Maximum bit rate = 1512 / 2048 * 188 / 204 * 64 / 56 * TBandwidth * Tcode_rate * TConstellation * TGuardInterval (bps)

= 423 / 544 * TBandwidth * Tcode_rate * TConstellation * TGuardInterval (bps)