Hi all,

I have run into an issue that requires some expert advice and would be extremely greatful for being pointed in the right direction.

Basically, my job has evolved from progressing a level 3 baseline schedule for the client to expanding details of certain activities to expand our schedule to a level 5. Here's an overview of what I'm dealing with.... 

1. The schedule has been built by estimators using internal phase codes that are translated right into P6 as Activity IDs and there are very few if any activities that deviate from that set system.

2. There are over 4,000 activities and there are nearly 11,000 relationships.

3. The dates are largely driven by owner furnished equipment delivery dates provided them and these are set as milestones. Essentially, the idea is to show that our dates are being pushed out by the owner's equipment showing up late.

So here's the example of my question. My boss wants the activity details:

40001     DELIVERY PM-1020 (Set as a milestone that drives all subsequent piping installation)
40001A   SET PM-1020  (This activity is loaded with the manhours directly set by the estimating department and the   duration is set by these owners on a 60 Hour work week.)

To become:

40001      DELIVERY PM-1020
40001A     SET PM-1020
40001AA   Draft and Submit Critical Lift Plan to Client
40001BB   Client Acceptance of Life Plan
40001CC   Moblize Crane and Set Vessel and Secure
40001DD  Platforms and Trim
40001EE  Insulation
ETC............

So how do I add all of those activities and leave the original dates, durations, resources, relationships, etc. entact as possible without just starting over which is impossible in an in progress schedule, at least for me.... I suppose what he wants is the 40001AA-40001EE activities to drive the progress of the single 40001A activity if that makes any sense?

It almost feels like playing the old game Operation... I can't really move anything around without messing lots of stuff up. I just need to expand what's already there without affecting what's all tied together too much.

I would greatly appreciate any and all help I could recieve.

Kindest Regards,
Mark