To be fair, the concern was they were not comfortable with 20+ sec block times by Aug, moving the bomb offset by 400,000 would make Aug block times stay in the 13-14 sec range and Sep block times could be in the 15-16 sec range, so if they wanted to slip the merge to Sep they'ld still be in the "comfortable" block times range. So merge could be in Aug, but could be in Sep.