What time the Tube opens in London?

Leave Westminster at 05:38 and take the Jubilee Line to Green Park. Change to the Piccadilly Line and take it to King's Cross St. Pancras, arriving at 05:57.

Leave Waterloo at 05:41 and take the Bakerloo Line to Piccadilly Circus. Change to the Piccadilly Line and take it to King's Cross St. Pancras, arriving at 05:57.

Allowing for Eurostar's 30-minute check-in deadline, the first train you could take is the one departing at 06:55.

I assume you read my post on your previous thread. You can take the bus from either Westminster or Waterloo leaving around 04:00, make one transfer, and be at St. Pancras International in 30 minutes.

Thank you Tim. I was thinking about the same 6:55 am train and be there 30 mins early. I thought about the bus too but it sounds more complicated and I dont' want to get lost. So I'll probably take the tube. Thank you very much.

Fernando, you're staying at the Premier Inn,right??
You'll have to take the Westminster station. I believe I read the Waterloo station is down/closed temporarily.

The station isn't far...about a 5-7 min walk, but there are stairs to consider.

Thank you Michelle, Hopefully it will be open by the end of August. But I will keep that in mind in case it is still closed.

Fernando, Since you orginally wanted to take the earliest Eurostar, I'll encourage you to not rule out the bus so quickly. The Journey Planner at www.tfl.gov.uk is what I used to get the Tube times and routes I posted. It also gives bus times and routes. After you are given timetables for a certain route, there will be links to maps for the departure point, connecting points (if any) and the arrival point. Try plotting a route, look at the maps, and then decide whether or not they give you enough details to put your mind at ease about taking the bus in the wee hours of the morning. If they don't do the job for you, then take the Tube and a later Eurostar.

Thank you Tim, That is an interesting website. Many choices and maps. I'll probably still take the 6:55 train, just to give me more time. I rather be early than miss the train.
Should I buy the tickes from this site or directly from Eurostar? I believe the only difference is that here they charge $15 dollars for shipping, but I get some free goodies right?

The fares are sometimes the same and sometimes different when booking with eurostar.com or raileurope.com. For an arbitrary August date I chose (19 August) they are the same for the early morning trains: $104. Book ASAP. The cheap seats don't last long. Yes, from what I've read on the RS railpass section, it looks like buying Eurostar tickets, and not just railpasses, will get you a discount in the RS travel store.