Thanks for the timely post. This summer (5 July) we will be traveling to Germany and it looks like the best train to where we are heading is ou t of Paris-Est.
I have been on the RAPT web site trying to figure out how to get there from DLP. This month the route is to take RER A just like you said into Paris, transfer via Metro to Gare du Nord then walk to Gare Est ... easy. But as I get closer to 5 July (can only search through the end of May), the web site is coming up with different routes - and not good times.
The train we want to catch to Germany leaves at 10:40, so we are planning to arrive around 10:00 to give some "just in case" time. RAPT has us leaving DLP at 5:08 arriving at 6:08 or the next option (which starts with Line 62?) leave at 9:25 and arriving 11:12 (does NOT work).
Since our dates are so far out, do you think that the schedules are not set yet, or are they planning on working on the A line and there will be alternate schedules?
Thanks for your help.