It was clarified that the "not lower than" condition is strictly interpreted as "greater than" in the Bitcoin Core source code, and anything that is "lower or equal to" is rejected. Post-softfork nodes increment the timestamp by 1 on each new block starting from Unix Epoch 0x80000000, which imposes a limit on the maximum number of blocks. However, the unit is now ~10 minutes instead of 1 second, which is a massive x600 increase in the amount of time forced to hardfork. The difficulty calculation will become astronomically high since pre-softfork nodes will think that blocks are arriving at the rate of 1 per second.