Time to travel from east nanjing rd. To Shanghai hongqiao railway station.

Hi!
We're currently in Shanghai. We have tickets from Shanghai Hangqiao station to Guilin. The train leaves Friday morning at 10:04. We are wondering how long it takes to get to the station from East Nanjing rd. via metro line 2.
I've read different things, some say it takes 2 hours to get there and others say it takes about 40 minutes.
Quick response would be very much appreciated!