There is a separate thread for 2017 E300s. No clue about leaseability in February, but last year they leased 2016s until the end of March or June (depending upon who you talk to).
Best deal is finding a vehicle as close to 3000 miles and negotiating a great discount on that. Residual Value is reduced $0.20/mile for each mile over 3000. A 10k loaner would have RV reduced $1400.