H1b extension stamping - query related to client letter

[kartz0108]

I am planning to go for H1b Visa stamping in India and currently in process of collecting the required documents, one of them being my client letter.
Now the issues:

1. My contract gets renewed every 6 months so the client provided a letter stating the project is good thru end of may 2019. will this be an issue? I have been with this client for 2 and half years now.
2. The client letter is digitally signed. Will this cause a red flag during interview?