Hallo,
On February 1st, 2017 I submitted a solution on Python, which was accepted with the time 0.9 sec.  Yesterday I optimised it and submitted, but got "time limit exceeded" message.  I then tried my original solution (from 01/02/2017), and it also exceeded time limit.

Questions:
1) has something changed in the methodology, or you added some new or modified old tests so it takes more time?

2) is timing dependent on the server load or each solution is tested independently on a dedicated thread? (THis may be a good question for the FAQ)

Thank you in advance.