Help Please

I have a multiplayer game running and we have hit a snag. The game was started in version 1.17. There is 8 AIs and two humans. We where playing along very well until the two human players became an alliance. Turn processing went from 1 - 8 minutes to hours (one was timed at 1 hour 43 mins.) This lasted for approx. 4 or 5 turns, then the process time fell back down to the 1- 8 minutes, but we have a new problem. Most of the ships on the map (including AI vessel we can see) are moving at a speed of one. We have tried cancelling thier orders and issueing new ones and this did not help. I had one vessel moving at my regular speed (15) I joined it in a fleet of ships and they all moved 15, when a removed any of the vessels from that fleet it reverts back to the speed of one.
Any ideas?

btw.... We upgraded to 1.20 approx. 2 turns into our long processing time period.