The original plan for the second leg of my trip included a Black See boat cross. Due to 2,5 days delay of the boat, compared to what was announced one month before, I had to change plans. Here is how it looked like before starting the trip:
The long line is the boat trip. On 29th November I still took the train direction Batumi but soon saw it was not realistic to be back on time without too much stress. I got out in Kutaisi and took a bus back to Tbilisi.
The line was replaced by a vertical line of my stay in Tbilisi (thanks Tamo!), plus a last minute night train to Yerevan. I had to leave land and fly to Vienna to recover distance/time. At the end, and unexpectedly the night train trip from Vienna to Zurich finished in Innsbruck due to snow. It followed by several train changed and I end up to arrive Bern only 30 minutes before the initial plan.