I'm not familiar with the traffic patterns there, what's the best way to get to Big-C on Ratchadamri coming from express way over Rama 9? There's no Phetburi exit, afaik, and the next exit at Sukhumwit is a very long u-turn line and I'm not even sure it allows me to get to the rightmost lane on Sukhumwit to make a right turn at Ratchdamri.

Assuming Sukhumwit exit, how much time would it take me on weekday morning?

Are there any other exits or approaches?

Phetburi-Chitlom-back of Big C sounds like the better way but expressway exits on Phetburi are all very far.

Alternatively, by what time parking lot at BTS Morchit gets full? 7 AM? 7.30? Is there any chance by 8? What about BTS Onnuj parking? Is it still available?

I hate this going downtown in the morning business.

There is an exit that gets you very close to petburi road and as you mentioned you turn left down chitlom and then right through the back of Big C.

However, I have only used this exit coming from Rama 4 direction towards petburi , not sure if there is one coming from the other way.

Thanks, just checked it myself yesterday, there's no exit coming from Rama 9, there's only entrance from Wittayu on the way back (from Rama 4).

Coming from the north there's a u-turn just before Sukhimwit exit but once you get there you might just as well turn right to Sukhumit and then right to Ratchdamri again.

Saturday traffic was still brutal - spent half an hour just trying to exit Big C car park. I've heard that Big C staff sometimes have to use paid parking elsewhere as Big C itself is not big enough.

This is ridiculous.