What is the best way of updating a project schedule in P6 Version 8.3?

Calling the attention of P6 experts and Gurus!

HERE’S THE SITUATION

A scheduling team is managing a bunch of projects for a client and is having massive challenges updating each of the schedule. There are six schedulers struggling to find a more streamlined approach to collecting update information from various contractors and getting their inputs into the P6 version 8.3 scheduling tool. The client has their own server housing P6.

One of the approaches that was used previously was not very effective. It was to send the contractors a P6 generated Excel file of Schedule Lookahead which they then fill out. The file is then imported back to P6. The thing is, it comes back with a lot of different issues. Sometimes, the scheduler cannot even import it back to the P6 database or it comes with plenty of garbage information. The varying version of the source database add to the trouble. On top of that, the tool requires that the Scheduler who generated the Excel file in the first