Roll back update

Does anyone know where i could a roll back to 0.9.1.5 since the server i play on is still on that version
ive gone into beta options in steam but there is no roll back for that version ,or could it be added to the steam drop down menu please

thank you

they have a teleport/bartering service running in the background and the update is causing issues with the bot
they have tried to update but no cigar.was just wondering if it was possible since alot of games out there have the previous version for these kind of probs
which allow you to roll back if needed
By the way LOVE this game!!!