Do not assume it extends the filing period. Track the actual conditional-residence dates and assess how to obtain and present the required evidence on time.
Resolve the relevant accounting issue early
Preserve requests, responses and the known state of the records. A completed reconciliation does not itself remove residence conditions, and an unresolved schedule does not guarantee extra time from immigration authorities. Deadlines in this process are set by status, not by accounting.
Conditional permanent residence begins on admission or approval of adjustment as applicable, runs for two years, and the petition to remove the conditions is generally filed in the ninety days before that second anniversary. Nothing about an unfinished reconciliation moves those dates. The practical response is to work backwards: identify the anniversary, identify the evidence the petition will need, and identify which of it depends on someone else producing records.
Then start asking early, in writing, and keep the requests and the responses. What goes wrong is a quiet dependency, where an applicant waits for a project to complete a schedule the project has no particular reason to prioritise. If the records will not arrive in time, that is a problem to raise with counsel while options still exist rather than in the final weeks.