Breastfeeding twins...HELP!

Renée
So I found out I'm pregnant with twins and I'm 8w5d. I had planned to breastfeed but with my 2yo who had tongue tie it just didn't work so I expressed (by hand) for 6 months. 
Now it's twins I'm guessing my hand expressing won't be enough so I plan to buy a double electric pump so my mum (who will stay for the first 3 months) and husband can also help with feeds. 
But will I produce enough milk to breastfeed and express or should I forget expressing and try to solely breastfeed? And will I have to wait for months before expressing?
Twin mummies, what has worked for you? Thanks