Well, things don't just happens overnight.
While I do agree with what utelore said, I think that's the best chance of Taiwan to put their air asset to its best use. The surprise factor will no work.
Weeks before the election even begins, PRC would've more or less guessed at the outcome of it, and would have prepared to strike/to defend way before the election is over.
Important sites would be fortified, or even moved to new locations(To avoid PB mode HARM), more SAMs brought in, more aircraft divisions moved to the strait. Essential crews would be on stand by mode.
Before giving taiwan the 72 hours warning, PRCs naval asset would already be mobilised to take up defensive positions on strategic points. Air patrols would accompany those ships too. All balistic missiles would be launched at a finger click away. And pilots would be sitting in their aircraft on rotational basis ready to take off at first sign of trouble
So I'm saying that 90% of the attacking force won't even reach Chinese shore. Most casualty would occur in the taiwan straits itself..
MY PLAY as PRC.
After which, the PRC can choose to NOT EVEN attack taiwan, to NOT EVEN launch their BMs, UN security council will definitely be brought in. The chinese would call for sanctions and etc. As ROC will be seen as the agressor the US would be in a hard position to defend them.
Talks will be held, for maybe weeks, the ROC freedom corp/armies would be confused at the political battle ensuing, most will even lost morale, blaming themselves as the agressor.
My agents planted long before the attack would now have the fuel it needs to sway public opinion. The population would be angry at the administration for causing 'shame'/sanctions on taiwan.
And if talks doesnt turn out well, I'll use force to attack. Now after weeks of 'diplomacy' surprise would now be in my hands, morale would be lower on ROC due to the negative international image/pressure/news coverage on them.
All the roadside bombs that utelore took days/weeks to prepare would've been discarded, as life went back to normal during the weeks of diplomacy.